Not a panic button. As far as I’ve heard it’s just a camera that only has a short recording time. If someone is benign abusive, you press the button to make it start recording. Either the abusive person will back down at the obvious camera recording them, or they’ll get more aggressive, but at least then you’ve got footage of them. The overhead store cameras are really crap quality.
Characters needing to talk “privately” when in a location with others. The solution is always to take a few steps in one direction. They’re still clearly within easy hearing range of anyone who isn’t massively hard of hearing. Yet apparently the other characters in the room all just go temporarily deaf.