We'd pay more to have our own bed, our own shower, etc. But when it gets up that high for camping - define camping? - I'll go find more boondocking areas or primative areas and enjoy it more anyway.
It's probably more the family with kids and specific vacation times that need the higher priced resort style vacations, even with camping vehicles. We could not tolerate that for long as we've been rustic camping campers for fifty or so years. It takes different kinds of areas, different prices to suit all types of camping and family groups.