While you can opt out, not every document check station has signage to that effect in my experience; the TSA individual only tells you to put your head in the c

While you can opt out, not every document check station has signage to that effect in my experience; the TSA individual only tells you to put your head in the camera frame; and most people have had An Experience with TSA officials becoming belligerent and even aggressive over small things. Frankly, it's intimidating, and I don't blame people for not opting out even assuming they know that's possible