Most people would stop at a store or something halfway through a 100 mile ride. Racers might go straight through on 2 bananas (when i was racing) or probably a few gels or whatever now. If you eat a pile of pasta or something the night before your glycogen will last longer before you bonk.

On a tour, I like to eat some oatmeal or other carb in the morning, stop somewhere for lunch of opportunity, and then cook something at camp at night. Additional stops at fruit stands and what not should be made as the opportunity arises. Enjoy yourself, that's the point.