Shop Helper / ElectronicArticleSurveillance

My idea is to help towards combatting shoplifting by turning the idea of crime prevention around. Currently when you go to leave a shop, if there is a tag still on the item the barriers go off. Honest people who have purchased the items go back to the till to get the tag removed so they can use the product. However shoplifters just carry on walking, very often without consiquence. My design is that the barrier sets the tag off, this is technology which is already use such as in panic alarms, and give off very loud high pitches sounds for a long period of time which would make it much more difficult for shop lifters to get away.