Korean man: Where you come from?
Me: Canada.
Korean man: Really? But judging your accent, you are Arabic?
Me: No, you mean judging from my appearance.
Korean man: Oh... sorry.
The Latin terms jus sanguinis (right of blood) and jus soli (right of soil) describe two alternate approaches to determining nationality. The former refers to citizenship being determined based on the nationality of the newborn child's parents. In the latter case, citizenship is granted based on the physical location of where the child was born.
When a Korean or Chinese asks the "Where you from?" question to an exotic being, what they are interested in is the blood and not the soil. What I hear is "Which country were you born in?". What they are actually asking is "What is your ethnic background?" or "Where do your ancestors come from?". These are perfectly legitimate questions, although white guys are never asked if they are really Scottish, English, French, Italian, or Russian if they say they are from Canada or America.
*****
All good people agree,
And all good people say,
All nice people, like Us, are We
And every one else is They:
But if you cross over the sea,
Instead of over the way,
You may end by (think of it!) looking on We
As only a sort of They!
~ "We and They" by Rudyard Kipling