It probably happens more often when the different stages of the pump are in different units. Fictional example: the archetypal Russian swindler used to sell the sandwiches his schoolmates freely shared with him back to them when they were hungry. Both legs of the transaction appear beneficial to the victim: feel-good sharing + hunger-quenching buy-back.
Neglecting time inconsistency, the net effect of that is that the other party gives money in exchange for feeling good, i.e. what anyone giving money to a beggar does.
It probably happens more often when the different stages of the pump are in different units. Fictional example: the archetypal Russian swindler used to sell the sandwiches his schoolmates freely shared with him back to them when they were hungry. Both legs of the transaction appear beneficial to the victim: feel-good sharing + hunger-quenching buy-back.
Neglecting time inconsistency, the net effect of that is that the other party gives money in exchange for feeling good, i.e. what anyone giving money to a beggar does.