What's the reverse version of the saying "既要做婊子，又要立牌坊"?
“既要做婊子, 又要立牌坊” describes someone commits to do something without the resolution of facing its consequence. For example, someone sells snake oil but feel bad about taking money from poor people (if you really want to be a con man, you can't avoid being ruthless)

The opposite expression would be "吃得咸魚抵得渴" (since you committed to eat salted fish, being thirsty is expected)