Yeah, but then you'll have some crazy folks looking for that... just like drug addicts want you to call an ambulance for free drugs.Maybe if the penalty were more like "cellphone confiscated, then returned as suppository on the spot" that might have a deterrent effect... and you're paying for your own proctology work to get it out.
The first few pukes get their phones taken away then shoved up their arses, and others might learn from the example.