I cannot IMAGINE telling a black woman walking on 23rd Street with her boyfriend to shut up and stop insulting gays. Or anything else, for that matter.
That’s not a mugging, and least not how I would use the word.
Mugging is when someone comes up to you, hits you without provocation, and steals your stuff.
I'd say the boyfriend performed an act of chivalry. Didn't realize there was a law against that.
Think of literary license and Kuby being mugged by reality.