I detest tipping, in the UK if it is exceptional I will leave 10%. Other than that I won't bother and I have no qualms about pressing F1=NO TIP, or asking them to remove the optional service charge if it has been added saying I will leave cash as the tip. In the US I am also getting fed up with the suggestions creeping up and in some cases starting at 18% as are my US friends. I'd rather just have it all included and know what I am going to pay - if they want to take the gamble on a tip then that is what it is.