I think the fnords are meant to have more effect than merely making most people uneasy or uncomfortable; they're supposed to function as a means of outright control. But I haven't actually read the Illuminatus! trilogy so I don't guarantee I'm right about that.
In Illuminatus!, children were trained to have anxiety reactions to fnords in elementary school, and then have no conscious awareness of why they felt anxious. I assume this is allegory-- and also that most of the training doesn't happen in school.
I'd say that in the book, fnords are about control, but in a general "the system is out of control you" sort of way rather than getting specific beliefs or actions.
Ads don't have fnords, so people buy things in the hope of relieving anxiety. This is not literally true-- many ads evoke anxiety.
Becoming able to see the fnords is a sign of impending enlightenment.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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