I just had a meeting with a client and we both paused to watch a group outside of the conference room present a cake to a group of colleagues. I made the comment that it seemed to be a pretty frequent event in their offices. His response: "Yeah, it happens all the time here, but not in our group. Our group is basically the 'Jehovah's Witnesses' of the floor. We don't celebrate anything."
Since he's never mentioned his religion, I've never mentioned mine. It gave me a good laugh, though. Just to be safe, I did ask him if that was because there were Jehovah's Witnesses in the group. He didn't think so. Better to know now if there were!