I've seen it in SimPE, too (when I was looking for a fireplace - can somebody please tell me what they're doing under "Unknown"?) - and my reaction was pretty much
because I've never seen it in game, either. It would be fun to see, though. I can just picture my Sim dad solemnly sitting his teenage son down when the son's asking permission to go out with his girlfriend.
And now I'm going to have to go back and have a closer look at it. (Well, after obeying my AV program and rebooting my computer, anyway, lest the thing's going to bug me about it every five minutes.