Anti-teenager device

A fellow in Wales has invented a device that emits a high-pitched noise to stop teenagers from loitering in front of stores. Since our hearing deteriorates with age, few shoppers over 30 can even hear the sound at all. I have to admit it is a clever concept, but given how much high-pitched noises can bother me, I can't really say I would be in favor of it coming into common use. Besides, small children out with their parents would probably hear the noise even better than teenagers. Think of the children, man!