If I were the parent, or the child, I would have had an earful for the guy. To the poster who said (I paraphrase) "It's a public place and thus he can do what he wants"?! On the contrary, because it's a public place, he CAN'T do whatever he wants.
And no, it was not Oui, and some might argue that Playboy has cultural significance. You're entitled to your opinion, but not to put material in front of a child or anyone else that they can't buy or wouldn't. It's the same as not allowing porn on public computer screens in libraries--at least at my hometown (not ORD) library, you have to use a computer in a cubicle to look at porn so that others don't have to see it.