Thousands of dollars???!!! That's hilarious. It doesn't cost thousands. As for lung cancer, dunno how well it'll work, but it certainly has healing properties for some skin cancers. I've never seen it sold as a "cure all", however. You might want to do a little more research before you spout the "evil weed" propaganda, which is completely false.
I think you should do a little more reality based research and drop your magical thinking.
As per price, the oil needs a lot of dope for extraction and it costs thousands.