The same people who are buying into all the ICOs, including the obvious scams. The following is my speculation only and not based in any real world data: Many

The same people who are buying into all the ICOs, including the obvious scams. The following is my speculation only and not based in any real world data: Many people have found themselves on the winning side of a high risk bet and their Bitcoins are suddenly very valuable. Some of them look to put a part of their winnings in some equally unlikely bet, and it seems like any unlikely bet will do. When enough people do this it becomes self perpetuating.