If they are going to charge for SAR, the risk should be shared. One guy getting a huge bill that he can't possibly afford because he sprainied an ankle in an area where thousands of others have hiked isn't just a deterrant, its borders on terrorism.
Some kind of insurance may be the answer.
http://www.backpacker.com/blogs/62
"Everybody is a potential victim; Not just the stupid.
To me, the solution isn’t self-righteous, free-market billing, and the lawyer wrangling that will inevitably result, its rescue insurance like they have in Europe. In the French Alps, for example, locals and visitors alike can purchase rescue insurance cards, renewable annually, for $30 to $40. That money trains, equips and funds professional rescue teams. These policies don’t cover medical costs. You still need a good health insurance plan, but the expenses of finding and evacuating you are covered, and a highly trained SAR infrastructure is created and supported."
From the same editorial, I found this quote interesting, although I didn't check their facts:
"But it’s easy to pick the wrong target when looking at SAR costs. For example, the major reasons for search and rescue call-outs nationwide are Alzheimer’s patients and ‘despondents’ (potential suicides). "
I was in the southern presidentials last August while there was a search and rescue, including a helicopter, for a possibly suicidal person. They looked for him for days and I'm not aware that he was ever located. If that cost is to ultimately be shared, it has to be among the entire community, not just some unlucky hiker who sprains an ankle.