I'm sitting at the airport with an hour to kill, so I'll pipe in. I think OP asked a simple fair question, can he opt out of camera. Then in typical Pinside fashion 50 people say "why would you want do that?", "just cover it up", etc. I guess the answer to his question is "No", but I didn't see one helpful Pinsuder refer to an owner's manual for an actual answer.
I think this simple question has received the full treatment by now, so here's another simple query: does DI camera detect only faces, or can you hold up a photo of a person, or mask, or cartoon or a poster? Not suggesting this as an option for OP, just curious if operators have to worry about obscene images or gestures, etc. Anyone have pics of funny images on a DI, let's see 'em.