If they point out the camera, how would they not notice it in the first place? With the tennis player, he's looking almost directly at it. And it's directly pointing at the front door. If it's compact, then you can just kick someone in the nuts, then point at a coke bottle and say 'there's a camera in that, you've just been kicked in the nuts'.

Catchy phrase, by the way.

"You've been kicked in the nuts." Original.