Has anyone ever been? Do you remember what/where you ate?
My fiance and I moved to the Tampa area from Tennessee, so every time someone comes to visit, we end up going to some theme park.
Anyway, I looked at all the available menus, and there were pretty much 0 straight-up vegan options. And most of the vegetarian options looked difficult to veganize. We're going on Thursday, and I really like to try to be prepared, instead of going from place to place looking at menus and making it seem like veganism is the most difficult thing on the planet.
Disney are frickin' insane in the best possible way about accommodating different diets. You could be a gluten-free halal kosher raw macrobiotic fruitarian and they would work with you. There is a secret all-vegetarian menu you can ask for in the Mexican pavillion and they will veganise it all for you. If you mention to your server that you're a vegan at any restaurant, they will be really helpful.
I was at the Brown Derby in MGM (years ago) and the server told me about the one vegan dish on the menu (some fabulous thai tofu dish, IIRC) and offered to bring out one of the chefs to arrange something else if I didn't think I would care for that dish. I know that's not in EPCOT, but that's just an example of how cool they are about it.
My husband and I were there many years ago and ate all over the shop. I didn't see any rolling eyes and nobody messed up anything and everybody was really friendly about it.