Hi Erin,
We just got back from a week at POP. As of now, you can buy a 24 pack of 12 oz / 355 ml bottles of Dasani in the cafeteria area (not the gift shop). It is $6.99 (same as 2 x 500 ml bottles lol). Find it in the back corner between the treat freezer and the staff door next to the baked goods (also same area as bottled drinks). The cases of water are on a shelf, and because there's only room for 4 cases, you may need to ask a staff person for more (they were able to go get some from the back for us). It was one of the best buys there for us. I started a free trial of
Amazon prime but honestly couldn't be bothered as there were only a few things we needed. We found the Art of Animation gift shop did have a slightly better selection of other sundry / "grocery" type items though (I saw Jif peanut butter there, and did not see it at POP). As you probably know, it's just a short walk over the bridge. Have fun!