: Try bringing along foods with low moisture content: dried fruits, nuts, granola, crusty bread. Of course, with all that dry stuff, you'll need water, which will probably get warm, but that beats warm soda...: Or, get spiritual-minded and fast. :)
: Have fun.
Also, if you can get them (perhaps at an Army surplus store?), MREs are excellent, if expensive (about $7 a meal). These are military rations, and come in vegetarian versions.
Get imaginitive. Do you have enough room for an iced cooler in the trunk? Keep canned soda (or, if you're interested in good health, fruit juices or canned tomato juice), sandwiches in zip-locked bags, etc. How about bagged peanuts, in the shell? A messy treat, but I like 'em. I'm also a big fan of beef jerky, but I don't expect the crowd here would be - a good road-food, though (popular with truckers). Don't forget a thermos of coffee, to keep you awake on the road. Shun alcohol (of course).
Your diet is limited only by what you can think up. No one needs to visit a fast-food store to profit from what a capitalist economy has to offer - plentiful produce and ample access to plastic goods, like Tupperware, makes the American tradition of the "road-trip" a most enjoyable experience, so long as you prepare properly. So enjoy!
D.C.
None.