It is not so much about your device being at many places at the same time (though it is a nice side-effect) as it is about polluting tracking databases. If you normally have 10 people in an area, and all of a sudden there are 2000, you know something is wrong. But there is no telling which of these 2000 devices is the real one, meaning you have to accept false metrics, or remove all of them from your system (including the real device).