Bloke buying my car last week, takes out his i-phone and snaps the VIN number. Teases at the picture to blow it up, and there it is. Tilts his phone horizontal, and there it is bigger. And all in his records ready to be sent for checking.
And that's just one reason. Oh, and my Nikon with the 18-200 lens on it, takes 500 calories a day to carry.