Sorry to rain on your ponzi parade bud. Will do it again every time. Better put that in your calculations.
Future variations on the CryptoDouble theme will no doubt be perfectly legal, and engage in full disclosure of how they work. Should you engage in tortious interference with their business, they will sue you until you are living under a bridge, where you will have little protection from the large numbers of people wishing to use an electric drill on your kneecaps.
I'm not one of those people, but I would definitely watch the video on YouTube.

As long as they disclose they are a ponzi, like weeklyponzi for example, it's just a distasteful form of gambling and I don't give a shit so we are on the same page. But please don't bring tort law bs into this for your own dignity's sake.