Yes, consider the small towns across the Plains states that will allow you to camp free in the city park.(or Jacumba or Octotillo, here along the Mexican border in SoCal) In return, you will spend your cash in the local grocery, cafe, bar, theater, or whatever. I see that as a win for both sides.

They seemed to have more hostels in California a decade or two ago. I stayed at nice ones in Hilton Creek (near Mammoth), South Lake Tahoe, Truckee, and San Clemente that have since disappeared The Sacramento one, which was handy for ending a Sierra trip, is still there.

Here's hostels that are run by one organization---wow, they are in clusters only in certain areas, such as California and the Northeast. The South is pretty much out of luck. http://www.hiusa.org/hostels/usa_hostels There may be private versions of the same type of place, too.