What about the pay phone loophole?

What about borrowing someone's phone loophole?

This will simply create a black market in grandfathered pre-paid phones.

There are differnet way to communicate with people, taking out prepaid phones is an inconvenience... at best. At worst I could see some ruthless types kidnapping some innocent bystander-just to use their phone but I'm sure they will also take the opportunity to rob them.

Thanks Schmuck.