You know, I truly believe some people get fooled by fake BBs, guys who advertise that they have BB in BJJ and then promote. Even those with legit skills that feel burnt because they were never ranked open a school, and just for the fuck of it say they are whatever belt. (I know a yellow belt (i think) that crushes purples and some browns that no one wants to rank -- but I digress).
On the other hand, some schools, the instructor is injured and never rolls with anyone, and I am beginning to see this a lot!
But also, the infamous BJJ police go after many folk who fake the funk, so other than those who are caught, I can see a ton of grapplers who got rank from a fake BB running around soon to find out their linage has a problem, a broken link if you will.