I agree about the Winn Dixie. Before it opened, I'd go to the Super Wal Mart on Irlo Bronson, a hike from the resorts.
The Winn Dixie was close and prices were great. My only complaint was they had a very slim selection of yogurt--my kids eat one particular brand (well, they'd eat the trix/starburst and other junky ones if I'd let them), but other than that it was great.
We bring a refrigerated cooler, and my way around that will be to stock up on the yogurts before we leave the gulf coast when we visit Granny!
Suzanne