The data feeding frenzy will not stop because people suddenly protect their privacy and eschew free messaging. It will stop because everybody already has all the informmation, so it loses its monetary value.
Facebook: I'll sell you Andrew Orlowski's complete profile for 5 quid.
Facebook: £4. Special deal!
His mobile phone provider, teamed up with Amazon: 20p. It's not our primay business, but we have it.
At some point there is nothing left to steal...