That's exactly what I've been doing for about 20 years as a matter of fact. No real trouble whatsoever myself, but I can't even count the number of times now I've seen people give my Chinese wife shit and then fumble all over themselves when I (an American) walk up and introduce myself. One old guy at a ramen shop even had the balls to try to explain how much better western and Japanese girls are, while she was sitting right next to me.