What happens when someone launches an App that the driver pays a few quid for to be a taxi at the weekend ? If Uber are prepared to go this far, whats to stop someone with less scruples going even further. Hoards of unlicensed jamming up the roads, fighting over customers ?
Personally I see too many empty mini cabs about already, a very inefficient form of public transport. I get the usefulness for disabled people, but it still another empty/ one person car on the roads.
I hope not, so I do think you have to draw the line somewhere