The trick to southern Utah is camping off national park lands. Or for us "non-old" people who don't get a national parks pass every year, it can be a cheap way to see some amazing things (see my avatar for example). The other trick for us youngsters is to go early. For example, Rmnp doesnt care if you enter before the rangers show up. They are also very vague on the hours they keep.
If one is willing to go without electricity, there are a plethora of "dispersed camping" sites, usually on blm land in southern Utah.
We got a "parks pass" this year. 3 months in we've only saved about $50. But, I don't have to deal with the ahole concessionaire at Brainard lake near Denver.