Ambassador, British Airways Executive Club, easyJet and Ryanair
Join Date: Sep 2011
Location: UK/Las Vegas
Programs: BA Gold (GGL/CCR)
Posts: 15,930
They are used to the Brits in there and so are not expecting tips, indeed the vast majority of users (including Americans!) don't. If the service is good (which it usually is) then certainly feel free to offer them a little gesture.