All food on the cruise is included except:
A charge for Palos brunch and dinner (I think it's $10 for each person, but don't hold me to it).
Pre-packaged snacks (bags of popcorn, candy, etc) sold outside the theaters before the shows.
Alcoholic beverages (except during the Capt's gala usually held on semi-formal night, 7 day only; and during the
Castaway Club reception for returning cruisers)
Smoothies
Soda (except in the sit down dining rooms)
Any food purchased while in any port besides
Castaway Cay, your CC meals are included in the cruise price.
Room service is included except for sodas, bottled water, or alcoholic beverages.
Fruit punch, lemonade, iced tea, coffe, filtered water and hot tea are available for free at the deck 9 drink station. Similar drink selectoins are usually provided at Topsiders for the buffets, as well as milk. I think there's usually juice there in the mornings as well.
The one thing you won't have to budget for on a cruise is FOOD!