A "real" supporter tag is stupid - do you feel joy/misery based on results? Congratulations, you're probably a real supporter. If you're worried about your association with a "brand" you're probably a glory hunter.
That said, and this might be odd coming from a foreigner since we're generally not supposed to agree with this line of thinking, I do acknowledge a difference in fans between local/non-local, or at least those born into support vs not. It changes the way you react to things going on at clubs in subtle, hard to explain ways. And I acknowledge it because of the provincial, tribal, local nature football has - or had, depending upon your cynical outlook at the globalization of "brands".
It's not "better" or "worse", and I think thinking in terms of that is stupid, but it is different.