Not even close.
Try "because we are familiar with many of them and know that their income depends on selling 9/11 conspiracy theories, not 'holding down a job'".
I was working in NYC this past Monday, 9/11! Most people who weren't directly affected by deaths in the WTC were at work, not hanging around the site sporting conspiracy t-shirts.
Your theory about refining their trial balloons here was quite an epiphany. I could never figure out why recent and even old sign-up-date trolls post their silly notions even though they must know they are going to be torn to shreds. Makes sense in a twisted way but makes me even more reluctant to feed the trolls!