Several of us have actually done this in reality (well not the risk-free part, we do take on a lot of risk). This needs to be repeated over and over until you realize that it is actually happening.
Some of us have become very good at picking who to lend to and who not to lend to. Just because you think it is too risky for you and that you would never try to do it does not mean you have to try to make everyone else stop doing it.
I have no objection to you doing it with your own money. And every explanation I've heard for why other people's money is needed fails the giggle test.
It's the constant need for new money after claims of making large profits. Tell tale sign of scam.