Imagine a German restaurant so named. "Best blood sausage in the East Valley!" Or MOM's Diner of Mesa. "Fine Aryan cuisine served up right by members of the militia of Montana." Would you be offended? I just made up those examples.
But this is a real example: La Raza Steak and Ribs, a Mexican joint in Apache Junction, Arizona. When I mentioned this to a friend, he replied, "That would be like naming a German restaurant Die Rasse, The Race."