Excellent reason. Let me add another: if earthly punishments are used to attempt to discourage behavior, this may shift people's focus away from avoiding the behavior and toward avoiding being caught. If people manage to avoid being caught by earthly authorities, they're apt to believe that they're getting away with their behavior. The message they should be getting, but which earthly attempts at enforcement will not convey, is that there's no "getting away with" anything in God's eyes.