So you are offering $500 dollars cash to go live naked for two days while eating fish caught by hand in the stream?
I guess you could say that. But it would be tough to do even that without utilizing petroleum. Especially since one need to document the 48 hours to prove they didn't use any petroleum.
Point being, in reality, it is near, if not impossible to do it.
Its a good teaching tool as most idiots think oil = gas. They don't think of the thousands of things they use and come into contact with on a daily basis that are made from oil.