Rad! I hitchhiked with a folding bicycle one time. Always talk with bicyclists everywhere you go, they can set you on the right track for bike trails and let you know where to go and not go. If you ever hitchhike, you'll have to narrow down your rides to trucks or SUVs that have enough space or cars with bike racks. Food banks are awesome for getting free food water's easy to come by. Recently, I was showed a wood burning, cell phone charging, camp stove that creates very little smoke. Food for thought.
This sounds like an awesome trip! Janktoaster has a point about the saddle bags. You'll find all sorts of cool stuff and acquire tools for shelter making and survival. With a bike, you can pack more stuff, especially if it's a touring bike rather than a mountain bike. I've also seen people pack stuff on the handle bars and on the frame.
When you're out there, if you start thinking what the hell you're doing and think about going home, don't do it. That's what started going through my head on my bicycle trip after a few days. I stuck with it, and the trip got way better the very next day. Then the trip got better and better. It can be a very worth while experience, even if it's not much fun. Having the stories alone are worth the experience.
Chances are, you could find a better job than grocery store, while you're travelling.
Bon Voyage.
