I just read online (http://rt.com/usa/news/investors-currency-digital-fund-868/) that somebody went and started a bitcoin ponzi scheme. Fairly natural, right?

What I am wondering is, if this was actually illegal, since the money was not "fiat currency." If it is, would that mean that a ponzi scheme based on, I don't know, WoW gold, would be illegal too? Does that mean all those websites that don't even accept money, but say "you visit this link, and the next 2 visitors will visit yours" are illegal too, because they are ponzi-ing website pageloads?

Just wondering. Either way, it feels weird somehow.