I always tip pretty well, but if someone asked for one I would tell them they just lost their tip. A tip is meant to be an indication of how much you appreciated the service not something they are entitled too.
I also don't pay the service charge (optional in the UK) as I prefer to tip the person direct.
And I agree with the Bar Staff tipping comment I used to manage a nightclub and we had girls walking out with £100+ in tips a night for serving drinks. Appreciate what you get if you get anything.
My mailman walks for hours everymorning to bring me my mail. He does way more work then the local bar person and he doesn't get fuck all from me for it
