Hi Glenn,
Bringing your own snacks is a great way to save some money on a
Walt Disney World vacation and to assure that everyone in your party is always well hydrated and fueled for fun. There are only
a few restrictions on what you can bring with you -- no outside alcohol and no glass, except for baby food jars. Otherwise, you are limited only by how much you want to carry. Details on allowable coolers and bags are in the link I provided.
I always tuck a couple of protein bars or breakfast bars in my bag. If you have a stroller, I'd recommend you fill a small soft cooler with cold juice boxes and drink bottles and tuck it into the stroller's storage basket. (If you freeze a couple, they can act as ice packs to keep the others cold.) Snacks can be in a backpack or tote.
I've seen families bring a loaf of bread and peanut butter or lunch meat to make sandwiches and even witnessed one family unpack an entire hot meal from a cooler.
Did you know that every counter service restaurant in Walt Disney World will give you a free cup of ice water? That's another way to stay hydrated without spending a lot of money.
Thanks for stopping by the Disney Parks Moms Panel with your question, Glenn. Please let us know if we can help in any other way as you make your plans. Enjoy!
Wilma