Black-Cab fares are a rip-off!
A black cab journey from Heathrow to my place (approx 12 miles) costs 45 quid. A private hire costs 20. You do the maths!
And the black cabbie keeps grumbling throughout (he would rather go to Central London and earn even more money). If a private cabbie makes a reasonable living by charging 20 quid, then the 45 quid shoud keep the black cabbie happy enough for him to go where the customer demands!
And what is the tip for? It's not as if the black cabbie would ever get down and help with the luggage etc. Tips should be for people in the service industry, who earn low wages and can make up by getting 'tipped' for good service provided. Not for black cabbies who earn a decent amount anyway.
Also read about black cabbies who fleece tourists by deliberately NOT going into bus-lanes (which they are allowed to), during peak traffic hours, seems it is more profitable for them to prolong a journey rather than take on new passengers.
Maybe it is just my experience, but the only reason I would ever take a black cab is if I had no other option (and to be fair, also for security reasons late in the night).