I am not sure what you mean by snacks.....all food is included which means all your meals, anything food from room service, all the "fast food" type things like pizza, chicken fingers (the best!), hot dogs, panni sandwiches, ice cream, fresh fruit, etc.
If you mean popcorn, pretzels, chips, candy.....they do sell those things outside of the Walt Disney Theatre. You could also bring your own "snacks" on board with you, but there is so much food being offered all the time there is really no reason, unless you want to bring your own popcorn to the movies!!
MJ