Ponzis are only illegal because they try to masquerade themselves as a genuine investment. Why is that so hard for people to understand? When everything is out in the open its nothing more than a game (unless the operator runs away, but anyone who handles other peoples money can do that)
If you're talking about the sites such as leancy, then you're going to have to prove they're a ponzi if you want to get anywhere.
How is it a game though? What is the objective? These ponzi threads need to gtfo of the gambling section they aren't gambling in any sense of the word. Your just transferring coins to a third party.