Me (as King's advisor): Well, you get to keep the treasure you find.
Players: We want some cash. Or some magic, up front.
Me (as King's advisor): Hmmm. You know those horses you have? If my troops were to check the brands, I wonder if they'd be from the merchant caravan that went missing?
Players: But we got them from some bandits we took out!
Me (as King's advisor): So you say. I'm sure the "real bandits" would say something similar. Did you know the penalty for horse theft in this kingdom is death by hanging?
Players: Hey wait a minute!
Me (as King's advisor): Of course I could overlook this peccadillo for those who give service to the Kingdom . . .