Transformers, Harry Potter..Doesn't ANYONE do a Standalone Anymore?

A couple of weeks ago I indulged in a summer guilty-pleasure, and what has become a tradition with me and my two kids:  we went to the theatre to see the new Transformers movie.  It began as a family outing to the movies - Mr. Grant gamely tagged along for the first one, but we haven't been able to drag him back to the theatre since. Every time one comes out, the kids and I make sure we see it in all of its big screen, 3D glory, then buy the movie on DVD when it comes out.  Before you all run away, this column isn't about the movie (although I do have to say that it was better than I expected, Mark Wahlberg was, ahem, a great casting choice, and I got to see Transformers riding Dinobots!)
On the way home the kids and I were rehashing the film and the three movies that came before it, and for some reason I started thinking about the sheer number of series out there - both in film and in books.
I have very mixed feelings about movies that become a series.  For every one that works really well (Star Wars, Indiana Jones and Toy Story, for example) there are lots that don't (Friday the 13th, Police Academy  and Rocky, just to name a few).  Of course, these are strictly my own opinion, and you'll notice that I haven't mentioned any films that were based on a series of books.  It takes a lot of talent to keep a franchise fresh, keep it interesting, juggle all the continuity threads and make us want to pay to see yet another adventure with the same bunch of folks.  Sometimes even keeping them the same is a challenge.  We've all seen  movies where one of the actors gets switched out, and I never know what's worse - if they keep the character the same and we all act as though we don't notice?  Or if they make a tiny tweak and the new actor becomes the cousin/friend/sibling of the character who has gone.  Neither is ideal - the former can be creepy and the latter simply lame.  
Same with books in a series.  For every series that is so well-crafted as to be virtually seamless, with storylines that progress naturally and characters who complete a journey during the course of the books (Harry Potter, John Lescroart's  Dismas Hardy and J.D. Robb's In Death series) there are those where it becomes quite obvious that the author has run out of steam, ideas and/or enthusiasm (Charlaine Harris, I'm talking to you, here) and keeps churning out books for no reason other than that fans will keep buying.  Lest you think I'm picking on Ms. Harris, I could also add Laurel K. Hamilton and J.R. Ward to that list.  I'll also add (sadly) Patricia Cornwell.  I love Kay Scarpetta, but I think anything that could have been done to her and her cast of sidekicks has been done at least once, including a truly jarring change of POV 12 books into the series.   (Please note: the authors and series noted above are books that I have actually read - it wouldn't be fair to discuss books that I have no personal knowledge of.)
If you look at the romance genre specifically, the series monster is running amok over there, with no signs of slowing down.  If I recall correctly it seems to have started with trilogies.  Standalones were pretty much the norm, but Nora Roberts started doing them in the late 80s/early 90s:  3 sisters, 3 three brothers, 3 witches...she pretty much had a lock on the whole thing.  Nowadays, you can't pick up a romance novel (whether it's historical, contemporary, erotic, paranormal or otherwise) without it being part of a series.
I'm not sure how I feel about this.  Is the standalone romance novel dead?  Is it really so hard to come up with new characters and stories without having them rely on events of the previous books to propel them forward?  If the stories are truly intertwined, with a specific world built for them and the author  has envisioned an epic story consisting of six, seven or even 12 parts, is that different than the trend that I'm watching in romance?  The one where the series is based on friends, or siblings, or a town,  where sometimes the only thing linking them together is a tenuous, peripheral link and/or a title that tells you it's part of a series?
Who is behind this trend?  Is it readers, clamouring for more and more of favourite settings and characters?  Or is it the publisher, investing in an author's name and pushing the limits of creativity in favour of a guarantee of sales? Or is it the authors themselves, for any of the above reasons?
Once you get talking about series, though, it becomes a steep, very slippery slope.  Do you include trilogies?  What about cliff-hangers?  What about the serial novels and novellas so popular in ebooks lately? What about P2P fanfiction - which, simply because of its beginnings on the internet, can meander about for hundreds of pages past where any self-respecting author or editor would chop it off at the knees (50 Shades, anyone?)
Speaking strictly as a reader, I can tell you that I suffer from a specific type of disorder.  It isn't unusual, by any means, but it lacks a universal name.  I call mine CRASOOO - Can't Read A Series Out of Order.  Luckily for me I am late to the series game, so most of the "big" series (Outlander, Karen Moning's Fever, Black Dagger Brotherhood, etc.) were well underway before I ever heard about them.  Easy to buy 'em in bulk, so to speak, and gorge myself on the books like chocolates.  With the advent of the ereader, it has gotten even easier to both pick up an entire series in one click and inch ever closer to personal bankruptcy, all courtesy of Amazon.
My point here is that it is virtually impossible to stroll into a brick and mortar bookstore or even to surf bestsellers on the internet  to find a standalone novel.  When you suffer from CRASOOO (pronounced just like kazoo, for those who wonder) a trip to the bookstore can be very frustrating.  Let me share with you my experience with reading series before I bought a Kindle, taken from my Goodreads review of  "Dark Lover" by J.R. Ward:  
"I hold out three days before going back to the bookstore to pick up Lover Eternal. I'm vaguely embarrassed but soldier on. I can't decide which is worse - buy them all at once or slink back in every few days to get them one at a time? How many clerks work there? Will they all know me/pity me by the time I've bought book 8? I've already suffered through this with 10 Sookie Stackhouse books, and have been in there 5 times for Diana Gabaldon. Why must there only be one bookstore in town?"
Of course, now that I have a Kindle, my bookstore shame is no more.
 The biggest thing about a series is just that - that it is a series, and there is an inevitable wait between books.  What used to be measured in years is now often measured in months, and in some cases, weeks.  Waiting for a new book from a favourite author used to be like the anticipation you felt waiting for Christmas as a kid.  Now, like everything else in our immediate gratification society, we need hardly wait at all.  
When once you simply went to the library or bookstore and grabbed something else to read while waiting for your favourite, now virtually everything on the shelves is part of a series.  I know of people who run SPREADSHEETS to keep track of the series they are reading and release dates for new installments.  When you have that many series on the go, how do you just enjoy reading a book for the sake of reading a book?  
One could argue (and I do!) that even with the proliferation of series out there, in practically any genre you can mention, you should be able to pick up any book in the series and enjoy it on its merits alone; that each book should have a separate storyline within the major arc of the story the author is telling.  Good crime series do this, so does J.D. Robb.  A good number of romance series do that quite well.  Unfortunately, I've picked up a good many books and gamely started reading, completely unaware that I have stumbled into a series partway through.  The result (for me, anyway) is a frustrating read, full of flipping pages back and forth trying to figure out what I've missed, and an eventual trip to the Goodreads website, where I usually discover to my chagrin that I've been trying to read book #4.  Rare is the book that provides just enough back story to satisfy those new to the characters, while not boring the crap out of the faithful who have been on board since the beginning.
Jeez, now I've talked so much I've forgotten the original point!  At the end of the day (or the end of this column, whichever is longer) I'm pretty sure my opinion about standalones and series is this:
1. Some stories beg to be told in installments.  The world-building is so large, and the scale of the story so epic, that it literally cannot be done in 350 pages.  I don't have a problem with that.  Sometimes I read them and stop after the first one, if the genre isn't really my bag, but most of the time I'll try them.
2. Just as the above is true, some stories cannot be anything other than a standalone.  Look at "Gone With the Wind".  I don't care HOW many people clamoured to know what happened to Scarlett when tomorrow dawned, did we really need to have "Scarlett" published?
3. Some authors are quite good at banging out a series.  I mean, if you create a family or a town that totally kicks ass, why would you leave it after only a couple of books?  I've collected quite a few of these babies over the years.  The problem comes when no one knows when to quit .  Sookie Stackhouse anyone?
4. If books are released as a trilogy, or a series, and come out one after the other, a few months apart, Bang! Bang! Bang! as a reader I feel manipulated, and the snarky little troll in my head starts whispering, "Cash grab".
5. Likewise, if books are released as a series and there is virtually nothing but the most tenuous of links holding them together, again, as a reader I feel manipulated.  I have an idea that almost everyone in the publishing industry is aware of CRASOOO, and I'd be a fool not to think that somewhere, someone is exploiting it.

Lots to ponder, tons to discuss. I've just scratched the surface and I'm interested in hearing what you think!