- Those who immigrate to other countries, for example to U.S. and become U.S. citizens. - Oversea Chinese and their young generations. - ..
There are so many Chinese who immigrated to U.S., Canada, U.K., etc., got neutralized and became their citizens (holding their passports). Quite often, you'll hear them said that when they were introduced or introducing themselves.
* For example, most of the people in U.S. or Canada are immigrants from other places (except Indians and other Locals?), so depending on where they or their ancestors originally from, that's how they normally say it.