Retired military?
Gov't
Corps of engineers, maybe BLM too have some pretty significant deals for certain people. (So I have heard)
Poke around a bit. Someone will know more
Yup. Get an "America the Beautiful" pass, available to everyone. 1/2 price camping in Corps of Engineers, Forest Service, and BLM campgrounds. Free "dispersed" camping on BLM land and most Forest Service too, no pass necessary.
