I only know one guy within earshot whose constantly a sadsack about the game "What are they doing???!!?!!" and I don't care for it and I don't think anyone around me does... but I sit behind the visitors and everyone spends most of their time PIing the other guys.
It may be pretty tuckish of me, but whenever you tell someone you're going to a sporting event, you say you're going to root for your team, not loudly offer constructive criticism for your team.