 The truth is this. You don't have to be a person on the run to need one. They're cheap phones that you pay for with a specific amount of minutes in mind. There's no address attached to them. You can't trace them down. And it's perfect for criminals, of course, who just toss in the fire when they're up to something no good. But there are lots of practical uses, too. You can use them for the same reason that the bad guys do, privacy. Say, for instance, you need to put your phone number online.