I have found, by being guilty of poorly conceived jokes, that the joke is usually only funny to the doer. The recipient often has quite a different view. The custom is childish.
It is a skill I'd like to not be skilled at. Humiliation is not fun or funny for the one who is humiliated. I suspect you'll have a much less flippant attitude when you are the recipient. You seem to take pleasure in the humiliation of another. Why is that?
I been the recipient a few times, it's not hard to go along with a bit of joking. What is so humiliating about taping a 'kick me' sign on someone's back? Or something harmless as that...
Put urine in the apple juice dispenser. Inflate some rubber gloves, paint scary clown faces on them and give them to children. Send "Sorry for your loss." greeting cards to patients families. Tell some patients that their doctor got his medical degree from an online school. Doctor tells patient "You have a strange disease and we won't know what it is until the autopsy."