The operator of these ponzi style games takes a fee (something else real ponzi's don't do), so didn't need to run away.
Everybody pays en somehow magically BTC appear from thin air to pay everybody's profit?
As said before, Ponzi's are scam by nature and designed to fail, one way or another. Sooner or later the amount of new participants starts to decrease what makes that the ponzi can not pay out the promised profit. Then the owner runs, resulting in a mass loss for the most of the participants.