You know, no merchant is supposed to charge a fee for credit card usage--for any card or the other. They can give a discount for using cash, but they cannot advertise it as "credit card use surcharge GBP3" This is global thing and in the agreement merchants sign. They of course put on the surcharge for thier transaction charges given to the bank and credit card company. Hope this helps.

NYC is adding credit card use in cabs too, but for some reason I feel bad using it because thet cabbies like to see cash at the end of the day. But watch out for those fake London Cabs.