I don't mean to come down on you, but don't you think your little poster/joke is a tad racist?
I thought the spirit of the Coffee Shop/Lounge was to be ourselves and get to know each other as we would if we lived next door, or worked together or joined the same gym....I don't know about you, but I would never suggest such a poster/joke to my neighbor, my co-worker or the person I workout with at the gym. (According to the OP's directions)
I'm not sure you are aware of it, but we do have some members that are black, and your poster has what is well known as a racist slur on the side, not to mention the verbiage on the joke itself being more suited for the FZ. I'm not sure our black members could come into the CS and enjoy each other with others making jokes like that.
Maybe the OP does not find your joke offensive, and if that's so then I guess you're certainly within your right to post such, but if I was black, I don't know that I would find the Coffee Shop very welcoming if jokes like that were the norm.