I've been called a sovereign citizen as an insult, though I'm just a voluntarist (not sure if ancap or generic anarchist), and that sometimes was past the point of me saying
things like “Listen here you little shit”
but I'll admit "the society" wasn't persuaded. Though sometimes it felt that possibly more than half of the people present agreed, but were confident that the majority doesn't.
It's actually a very good propaganda strategy - even if most people disagree with you (as the bad guy), what's important is that they believe that others agree and thus keep their heads down.