I think you're repeatedly resorting to all manner of generalisations. Maybe that's your experience, and all that you've seen. While I've seen a bit of that too, I've also seen quite the contrary, very smart and learned people scientifically exploring fringe approaches in order to obtain results.
I could give you some personal and near examples of that if it were to mean something.
There's also quite a lot in natural medicine (including papers and proper scientific studies, if that's the only thing that matters to you) if you look into it.