Disney has such a large library of animated movies, most of which I'm sure would make great rides. How come very few of them aren't? Does it really all come down to how much money they make?
That can't be true.. If that were true, we wouldn't have Splash Mountain.
I think the whole thing is that the cartoons all mainly are in Magic Kingdom, which is now just about full. Heck it has a butt load of attractions centered around cartoons.
Hollywood Studios was designed I believe more for the live-action films, but also features a few of their hits like Beauty and the Beast, Little Mermaid, and even has Art of Animation.. But cartoons aren't what I believe Studios was originally intended for and therefore does not have as much of a toon atmosphere.
The same can be said for EPCOT. Originally have NO toons based off of Disney movies. It is slowly gaining some toons in the parks, but, like you mentioned, only the ones that make lots of money (Lion King film, Finding Nemo, Frozen)
Animal Kingdom, AGAAIIN... Not really a park focused on Disney movies/cartoons per-say. Even though classics like Robin Hood Rescuers could easily be put in here.. I don't think thats what the original purpose was. Even DINOSAUR was originally not based off of the movie when it first opened. A Bug's Life wasn't what I believe PIXAR's biggest success but it works well here. Also you have the lion king and at one time Pocahontas had a little show, and of course there's Nemo again.. But again, not really the purpose of the park's original intentions.
So yea, thats what I think it is. Magic Kingdom has all the toons, while the other three theme parks are slowly changing into MK #2, #3 and #4 as time progresses.
Anoooother thing to look at this.. This goes with your "only the movies that make big money" part. You would be incredibly SHOCKED as to how many kids AND teens have not seen the popular Disney classics... When I was touring our Aladdin show to 30+ schools, I would always ask the kids I was directing if they have seen the Disney movie of Aladdin.. About 28 out of those 30 schools had a majority of kids say "no." Followed by "But I like Frozen! And Finding Nemo! And Big Hero 6!!!"
Most of this new generation up to the age of say, 17, haven't seen movies like Aladdin, Hercules, Snow White, Cinderella, Sleeping Beauty, Peter Pan... Heck, half of the time nobody's even HEARD of Atlantis, Oliver & Company, Treasure Planet, Dinosaur.. It's kind of shocking. And even now, I'm STARTING to hear kids say they haven't seen the 00's such as Lilo & Stitch, Emperor's New Groove.. Ect. So yea, popularity really does play into affect as time goes on.
On the other hand, Beauty & The Beast, The Little Mermaid, Toy Story, Finding Nemo, The Lion King... Those are still quite popular. Therefore they still have a larger presence in the park.