Re: It's all about control
"If the hire company gets a complaint from a passenger, they are supposed to track that sort of thing and discipline employees"
Unlike Minicabs - which _must_ be centrally booked and dispatched, the vast majority of black cabs are owner-operators or self-employed in a hire taxi with no tracking of who was taking what fare where.
So, when someone complains about anything committed by a black cabbie, unless they have the taxi number AND the driver's ID, they're essentially untraceable.