When I had a less expensive Dash cam, which look liked a dash cam, with the wires sticking out of the cigarette lighter, I would disconnect and put in the glove department. Now with a newer more expensive one hiding in front of my rear view mirror , and the wires hardly visible, I don't care. My Iroad at the front of the car, doesn't look like a camera. With its its tub like appearance, if visible, looks more like a transponder or automatic starter. I turn of the flashing security light. With its stealth like appearance, it came in handy when there was vandalism between mine and my neighbors home earlier in the year.
I am finding when tailgaters notice a camera all of a sudden when they get too close. I have seen cases where tailgater back off when they see the small camera at the back.