Oh, come on... Let your dark side rule for just one second and enjoy the moment - haven't you ever wanted to, for just a millisecond? To be sure, you felt guilty afterwards, but the thought was there never the less. You never told the other crew members, or your partner or friends, but sometimes you fantasize about decking the one that has seemed to be intent on making every aspect of your working life a misery?
Just having fun - I don't really want to attack customers!