Almost every weekend, you get an AFL, NRL, Rugby game where some guy gives the"adoring fans" of an opposing team that "up yours" gesture after they've scored a try DURING the game. Why don't you ask those guys why they don't do it at the beginning or end of the game in front of their "adoring fans"? You are clearly missing the point.
I frequently hear threats through on field microphones in footy games and cricket about threats to the physical welfare of opposing players that have been far worse than a little dance. Geez... if you're worried about a little celebratory dance, don't watch these games, in fact, you should steer away from all contact sports and go and watch lawn bowls instead.
