Schu -

Lemme tell you a story about a "cheepo" hotel. On my first cross-country tour I stayed in the Sacajawea Hotel in Casper for $5 - yes, it was 1987, but still $5 was cheap. Of course, it was filled with winos and bums and the room was super funky. I put my tent fly over the bed and put my sleeping bag on top of that. Then in the middle of the night I heard a ferocious row going on. Turns out that two beat-up old drunks were parting company as a couple in the middle of the hallway - fighting over the ownership of a pathetic pile of possessions. I recall saying, "You pays your $5 - you gets your $5 worth."

I agree with Machka that hostels make a nice break, but I find camping preferable to motels not just on cost alone. I sleep better in campgrounds than motel rooms plus get an earlier start the next day. I can't tell you the number of times that I've listened to the TV in the next room past two in the morning or had someone warm up the diesel truck to go fishing starting at four.

There are three major public lands agencies in the West:
NPS - National Park Service - where you must usually camp in designated sites
NFS - National Forest Service - where you can camp anywhere
BLM - Bureau of Land Management - where you can camp anywhere

The "rule of thumb" >>> NPS - the spectacular stuff, NFS - the nice stuff, BLM - what was left over.
If it's not fenced or posted , then you can assume it's public land, also a lot of BLM land is fenced for grazing, but it still open to public use.

Small town parks are hardly filled with rowdy locals, small town police generally don't permit errant behavior to continue for long. More likely, you would get the 10-year-old kids doing the 101 question routine - but the camping would be fine. Also, in the Midwest and east there are often rural county parks that have limited camping - these are very pleasant.

Enjoy your trip. J