Meter Tariffs are set by the licensing authority NOT cabbies or cab companies,
I deal with the person I'm handing the cash to. Genuinely sorry to say that the days of me tipping drivers are long since gone. When I'm being charged nearly a tenner to get a run up from the rail station to the 7 dials there is none spare for tips anymore. Okay, not the drivers fault but I deal with the person whose pocket the cash goes in. If the the driver has a problem, his gripe can go to his immediate contact too.