An unsolved mystery!!!?

Since time immemorial, well since I've been driving anyway, man has stared in wonder at the spectacle that is the magical car key fob, press it normally and you must be within 3 feet of your vehicle for it to work, raise it to your temple however, and lock/open your vehicle from 20 feet or more. "no way" I hear you gasp, "yes way" I reply. There are 10 lovely points for the person who can explain this amazing phenomenon the best. Get scribbling!