I've seen it here n there. And swift, consistent mod action will obviously discourage it. So it it somewhat a case where absence of evidence is not evidence of absence. On the other instances I have seen a lot and it looks to be very difficult to effectively moderate once the claws get in.
But I agree with you that this OP is confusing and unhelpful. I have no idea why (or even if) anybody thought this would be productive towards the stated goal.