Cool post! Great theory.
Yes, it's quite strange. Alcoholics and drug addicts don't troll AA and NA sites with anonymous ID after ID to post vicious ad homs, attacks and criticisms, nor do they start and maintain daily blogs bashing at individuals in support groups that contradict their addictions. It seems to me that addicts couldn't care less, so it's not a general addictive response.
I used to think it was mainly OSA folks trying to disrupt things. That accounts for some, but not the rest - the Indies, FZers and 'I'm out but not really out because I'm still in' cult diehards that seem to come here for no other purpose than to spout venomous general accusations and denigrate the cult survivors.
Some FZers, like Terril, are upfront about why they are here and make an effort to be polite. Discussions of scn go in circles of course, but folks like Terril aren't mean-spirited and a lot of FZ members on ESMB are pretty sweet. Even 'OldAuditor' wasn't too bad overall, though some of his last posts were so condescending to exscn members that he caught some kickback. A practicing scn posting to exscn members about his concept of personal superiority is obviously not going to go over very well here. I can't even imagine an alcoholic boasting about his superiority as a drunk to members of an AA site, that's how weird it is. And yet we try our best to be nice to the mean ones who start up out of nowhere raging at us, anyway.
Getting back to your theory, yes, I think it is some sort of knee-jerk, trained in reaction that some deeply indoctrinated Scientologists have, like a sort of Pavlovian response. Maybe when something about scn doesn't meet their lofty expectations, exscns become their "why." It's like scraping your car on a curb and then blaming the shopping center for putting it there. It doesn't have to make any sense - it's Scientology.