Yes egg in hair is a greater level of violence than two straight punches to the face and six Nazis choking you out.
But, I bet he still thinks it was worth it. ...No, I'm not advocating "political violence." Though, egging someone --as a way of showing one's disapproval of a political opinion (granted an opinion about a vicious mass murder) is something better to encourage than the alternative of using mass murder to make a point.
So much for "moral relativism," but what would you rather have happen to you? How should we respond to "political violence" if it includes egging? Of course, if the penalty is the same for all forms, then it won't stop it. Instead, offenders would feel that there's no point in half measures. Why not throw a shoe or a rock or a bullet. They're all the same. No? Well, I think it's dangerous to equate egging with assassination. Ymmv.