Certainly the thing that always got my blood boiling in the past was GMs getting off light, despite a punishment defined in the rulebook. None of us are perfect, and there's no reason to expect a GM to have an entirely flawless career, especially if they hold the position for any significant length of time. Despite this, some people seem to have this notion that punishing teams as per the rulebook is somehow "cruel and unusual", when it's simply the game we're playing. Sure it sucks to lose $500 to a community chest card, but it's just a function of the game, not a life sentence.