A good natured jab is not the same thing as being mevayeish someone b’farhesiah. I do not believe a Gemara in Kesubos would countenance doing such a thing. It’s one thing to talk about the chosson’s bad-haircut days in his youth – quite another to say he looked like Alfred E. Neuman, and we can’t fathom what the kallah sees in him.
If this is a practice today – stop it in its tracks. Embarrassing someone in public is = murder. The words cannot be undone, neither can the potential loss of dignity the person suffers, as well as loss of reputation. Even “grahmin” should be written thoughtfully and sensitively with gentle humor.