I don't know defrauding 1000's of people for years while keeping everyone in the dark including most if not all of your employees and making yourself look like a functioning legitimate business as far as casual financial inspections go sounds pretty hard to me, at least as hard as running an actual investment fund.

Regulators probe the market constantly if your trades don't add up at all you'll get caught in a minute lasting years and managing to steal 100's of millions or even billions of dollars doesn't seem something anyone could just pull off, I think you underestimate the intelligence and skills required to run these sort of scams.