I don't ever recall anyone hitting someone in the head without a helmet with a weapon. In hockey there have been incidents of charges filed.
If you think kicking someone in the thigh or crotch is the same as hitting someone in the head with a helmet, you are mistaken. This is why there are rules in football about hitting someone in the head but not about hitting someone in the thigh. It's just flat out dangerous. Even in bar fights the criminal intent of truly injuring someone is taken into account. Punching someone vs. hitting them with a bottle or chair results in drastically different punishments.
Rudolph should be fined as well as the other players for what he did in the fight as it was a fight and outside the context of the game. However, absolutely nothing anyone can do should result in what Garrett did. Not to mention Garrett's history of fines and punishments in the context of game with late hits and personal fouls. He's going down the path of Vontez Burfect.