One thing I have tried to teach my kids is that there isn't anything someone else does that releases you from doing the right thing. Just because someone else is a rude sob doesn't make it ok for you to be one basically. If he grabbed me I think the rules might change a bit, I'd definitely be tempted take his props out.
People are weird at auctions, be a good place to do research for a term paper if you were a psych major.