Its very easy to take things out of context or make assumptions not knowing ALL the facts. For starters you don't know if he was "sent-off" or just asked to leave the field of play until he has removed the piercing. And even if he was "sent-off" you don't know what the ACTUAL reason was. It looks like an experienced referee who knows how to apply the laws of the game. Generally speaking wearing piercings warrant not allowing a player to play but does not warrant a "send-off" (red card).