the classical scam where somebody is selling illusions preying for those who want to buy illusions instead of looking clearly at reality
rationality helps a lot in these cases
In other words, people who get scammed are the ones who try to scam the other side most of the time. Don't tell me they are innocent ever. No. They want something for nothing just like the other dude. In the end since both of those parties can't have something for nothing, one of them will have nothing for something. Basically the tldr of scamming.