I worked as a fry cook at Yellowstone last summer for three weeks before I quit (I wrote about it here). I hated it for a few reasons (the work was exhausting, I got a MIP charge on my second night there, etc.) but there are plenty of people who come back to work every year. The job didn't pay very well and a large percentage of my paycheck went towards paying for room and board in the shitty company dorms. If you really like hiking, can deal with exhausting work, and don't mind that the only thing to do every night is get wasted, the job might be a good fit.
The Safeway dumpster kicks ass. I got cases of odwallas. I think some of the motels right downtown rent by month fairly cheap. Bus around town is free. It's a tourist town, if you don't mind that, the setting is majestic and you could probably make decent $ in a construction job around there, building faux log homes for kazillionaires
What about cover/concealment for camping? In Colorado ski towns, most of the time there's timber near town where you can set up a tent semi-peacefully.