!doctorwho
A good old fashioned Doctor Who Community
Not that it's especially convincing but I think that the idea was that he was 'playing a game' when he'd been doing that stuff with the salt and then thrown it out into the ether for no reason other than messing about.
Or something? I don't know. Much as I love a lot about RTD as a writer, he's definitely not a details man on story elements...