Because I'm a Quebecer, people often mistake my accent for an Irish one. Sometimes they ask is I'm from America to which I usually answer that, yes, in a way I am from America, America being a continent..
Because I work in primary schools and high schools (KS2 to KS4) I always get all sorts of questions, a lot based on false, preconceived ideas...and I answer the same questions over and over again, with a smile, giving every one a chance to learn about who I am, where I'm from, why French is my first, language, etc. One time, we talked about ice hockey. They asked if the teamed I played for had a fat goaltender like in the "Mighty Ducks" movie. I told them I was the goaltender.
But we had a good laugh and now, they know better.
Every time you live abroad or visit another country, you are, in a way, an ambassador for your country and your people. Just remember that next time your asked an "irritating" question.