IMO, there is no "starting it". There are always businesses that do that. Playing on whatever gimmicks they can to drum up business. Some more honest than others.
This is true, and I have watched youtube videos of one of the more popular Idaho ones, and he seems to be honest and upfront, and also says he will help anyone, including people looking to avoid conservative towns/neighborhoods.
IDK, in many ways, I just don't see this kind of segregation as a bad thing. I was pretty miserable in CA my last few years there.