I think the guy that beat up the vet is wrong, when you know that you can oppose your will on a person you should restrain from resorting to violence or fighting. Be the bigger man and back away and call the cops and they will take care of things. It's only a car and that's what insurance is for. I'm not saying the vet is in the right because he was absolutely wrong for defacing a persons car and those remarks are abhorrent.
If a guy did that to my nsx I would of called the cops, take down his plates and asked him to stay. Maybe even think about about repainting my car championship white. I would only resort to violence or fight to defend my friends and family from imminent danger. I use to love getting into fights and thought nothing of it but the more I train the calmer I become, I have walked away from quite a few fights I could of dominated. Just walk away because you never know if the other person has a knife or a gun, things can get ugly really fast.