We are AP holders to Sea World, and I bring in little snacks for my girls all the time (but we either eat meals in the park restaurants, or keep our cooler in the truck and return to eat). They don't do the world's best job of checking. I use a diaper bag backpack (that looks like a regular backpack) and put the little snacks in a hidden pocket. Don't know if that's ok or not, but I would much rather have my little ones snacking on organic crackers than funnel cakes, especially when they're probably going to have pizza for lunch.