Just got back from Aug 9-16 with DH, DS 14 and DD 8. First of all let me say, my kids are NOT big eaters and vacation is for fun--not healthy food!

We ordered:
Case of Mountain Dew
Case of Diet Pepsi
Case of Bottled Water (I'd drink some out of a bottle then freeze it to carry in the park the next day.)
Can of Pringles
Bag of Lays potato chips
12 count box of Pop Tarts
Bag of M & Ms
Package of Chips Ahoy Cookies
Gallon of Milk
2 bananas (but wish I'd ordered one for every day)
Lots of junk, I know!! I'd order the same next time but 2 bags of chips and 2 Pringles. (They were gone too quickly.) Less Mountain Dew and get Powerade instead. (My son kept buying it at the parks! $$$$

) I would have ordered breakfast cereal but I knew the poptarts would be easier--since we're usually dragging the kids out of bed and trying to get them out the door in the morning.
Next time, we all agreed we'd like more "lunch" stuff. In the summer we like to come back to the room in the afternoon so it would have been nice to have a loaf of bread, some deli meat or hotdogs to eat a quick simple lunch.
For me the water purchase alone is worth it. I drink a lot of water and it's just too expensive to buy in the parks.