I ride the Pittsburgh/Connelsville section of the GAP weekly and the entire thing several times a year and never carry food, there are more than enough trail side options for sure. I've never been received with anything less than a smile when asking a business to fill my water bottle either but water gets a little harder to find between Rockwood and Cumberland. Food is a little more challenging on the C&O, how you deal with food really depends on the experience you're looking for, I'm not into camp food. I wholeheartedly agree with fenders but that's a whole different debate.