This post could fit under many boards here at MC, since I believe it applies to Disney's movies, parks, and products in general.
In issue 171 of Game Informer, Shigeru Miyamoto (creator of Mario and Zelda) says "I could make Halo. It's not that I couldn't design that game. It's just that I choose not to. One thing about my game design is that I never try to look for what people want and then try to make that game design."
That is why Walt Disney and PIXAR were so successful, people weren't wanting a feature length animated movie or a theme park where rides tell stories, but Walt gave it to people. When a company limits what it does to what will be a sure-fire hit, then creativity is serverly limited. Submarines Voyage without Finding Nemo (though i do love the movie) could have gone in all kinds of directions (with wonders such as mermaids and a giant squid), but it had to be Finding Nemo Submarine Voyage so it would be a surefire hit. This made the Imagineers make an attraction the public wants instead of something they wanted. Brad Bird, says he makes movies for himself, and that is why his work has such great quality.