I was somewhat surprised to find a service charge added to my bill at cafes & restaurants in London recently. The first time this happened, I had already calculated the cost of my coffee and had the exact cash ready. The waitress said that was OK as the service charge was optional. On my last day in London I was trying to use up loose change and again had the right coins but I was told I had to pay the extra 69p for "service". The cafe already charged extra for "eat in" and the service was terrible but I paid up. What do most Londoners do?