We usually buy them at lunch time, at the restaurant of our choice - then we finish our touring for the afternoon - and on our way out of the park - grab an ice cream (if we are hungry) or some popcorn (if we're not - we save it for later). We also take our bottled water/soda with us to leave in the hotel room!
Another point - This is a LOT of food, depending on what/where you choose! We split 2 adult meal and 1 child meal deal for our family of five at the Flame Tree. We got the rack of ribs with a large lemonade (and this is LARGE), and the 1/2 chicken dinner with a large diet coke. We also got the children's hot dogs (with my 6 year olds voucher) for my 12 year old to eat since she won't eat anything with flavor or sauce on it! My DH drank the coke that came with the kids meal
So - DH & my youngest split the rib platter - and were FULL!
My oldest and I split the chicken dinner - AND WERE FULL!!
My middle daughter ate the kids meal - and WAS FULL!
The lemonade was poured into our water bottles (filled 3 small Nalgenes!) - we only got through 1/2 of the Diet Coke between the 3 of us that were drinking it!
Then on our way out of the park - We got 3 ice cream cookie sandwiches to split, and 3 bottles of water!
They are an awesome deal!