Hah. I've always wondered about INFJs. I'm a member of the FB groups, and it is obvious to me which ones are displaying Fi and Ne, and which ones are displaying Ni and Fe. Or even worse, the Si doms that think they are Ni doms. I think it's cute. Well no, not really, actually.
As I said in my first post on this forum, INFJs are highly fetishized because they are seen as the most unique, or "rare". Thus, a lot of people flock to that type, and claim it as their own. Of course, there is a possibility that they have simply been mistyped, but I think the former is more common.
Aaaand then you have the INTJ, which seems to harbor the racist, sexist bigot. Or does it really? INTJ is seen as the most "intellectual" to a lot of people, and rational, so people mistype themselves as such because they want to justify their irrational beliefs as rational. Protip: Your excessive amount of confirmation biases
doesn't make you very rational, you twit.