We have been full-time for 11 years and have never paid over $38.00 for a night of camping with our motorhome.  We use Passport America for 50% discounts, have used the Good Sam discount, stay in Corp of Engineer parks, county, city parks and smaller mom & pop campgrounds.  We seldom park at a Walmart and have never parked at a truck stop.  There are plenty of less expensive places.  Of course rates would be higher for a vacation to a special place, but I'm not on vacation.  We have full-hookups 99% of the time.