About Integration in Japan

Last weekend I met Hans from Germany. He lives in Fukuoka for 17 years and got married here 10 years ago. So I guessed he' s well integrated in Japan, because he speaks fluent Japanese and he knows all the customs and tradition. But he told me that he sometimes feels like an typical gaijin who can't eat with chopsticks. For 10 years he used to go to the same convenience store with always the same staff. But he always receives a knife and a folk when he buys food. When his wife cooks the meal she gives everybody chopsticks except Hans, although I told her that I want to eat like a Japanese. That's soooo frustrating 0^0