How cheap are you? Things that are easy to cook on the road, require no refrigeration and available from grocery stores:
Oatmean the instant stuff or old fashoned stuff packed in sandwich bags.
Macaroni and cheese
Canned beef stew
Raisins or other dried fruit
Weight Watcher full meal bars
A quick meal, package of Ramen, can of boned chicken, can of vegall, tobasco, salt and pepper to taste. Takes five minutes
A quick breakfast, 1/4 cup oatbran, 1/4 cup raisins, 2 tablespoons sugar, 1/4 teaspoon cinnamon, 1/8 teaspoon nutmeg prepackaged in a ziplock bag, 1 1/4 cup water. Bring water to boil, add contents of bag, simmer 5 minutes.
Cowboy coffee - 1/4 cup coffee, 2 tablespoons sugar in ziploc bag. Bring 2 cups water to boil, add contents of bag and let steep 5 minutes. Filter coffee through a piece of screen or your dew rag.