I don't think there would be any benefit to adding them on to the wall. It would look less professional, for one thing -- unnecessary modifications always do. Also, most people, it seems, follow the rules just fine. I doubt that seeing rules plastered on a wall will deter a young hoodlum... people who deliberately mic-spam and swear and such don't do it because they don't know there are rules; they do it because they are rude.