Mmmhh.... I guess, they know that there is a risk!

But that is not the case! I am sure, the way how they generate the miles is legal (or not against the T&C from krisflyer). I am also sure, they will do it over a credit card and transfer than the points from the credit card to the Krisflyer account. But I have no idea, how exactly (which credit card over which system)