The pandering of such BS is really just a platform for hateism or whatever you wish to call it. That sounds a little OTT, but since you did withhold your, uh, psychoanalysis of the problem, then I can't really say how it coincides [or doesn't] with your view on it.
What I'm saying here is that by presenting their opinions as though it were fact and successfully suckering in more people to agree with said 'fact', it gives them a safe refuge [majority rules] to potentially attack [troll, flame, what have you] anyone whose opinion runs counter to their 'fact'. Also, it helps if the people who start spreading said 'fact' are more established [or at the very least visible, or known] members of a community where people don't really know each other [like the Temp].
Then, of course, if said endeavor works, even partially, then the next time they have the opportunity to spring forth their 'fact', they've already got backers. Even locking up a thread rarely stops it, since the majority of the people in the thread who got suckered in, would then attribute that to the people with opposing opinions, because without people attacking their 'fact' with opinions, a torrent of abuse would not be needed [which is, of course, laughable].
This accomplishes two things, really. Establishing said opinion as 'fact' and spreading it out to others, and also fending off dissenting opinions. Basically, this is the reason one can't stop it.
PS
I'd love to read that 'psychoanalysis' of yours.
] 