Try not to snoop on drivers.
A McDonald’s employee shocked the world (!) when he revealed employees can hear in your car from the moment you pull up. “The speaker is activated by the metal in the car, so as soon as you drive up, the speaker turns on in our headset,” he told Mental Floss. “We can hear everything, and I do mean everything. Loud music, yelling at your kids to shut up, etc.”
Source : Goodhousekeeping
