I went to college with a girl with a German surname, about which she was often asked. She always replied that her Dad was indeed German and had been a prisoner of war working on her grandparents farm in Yorkshire, where he had met her mother. My BF has an unusual surname, and if she books for us to go anywhere in her name, again, she has been asked its origin. She is more than happy to say that her DF was Polish. It used to happen a lot before chip and pin, when her signature had to be compared with that on her credit card.
However, I cannot say anything to defend Susan Hussey, whose behaviour was simply out of order.