Exactly.I hardly ever use busses and for when I do I have an Oyster card. Some of you are making the assumption everyone thinks ahead like we do, and also that they are able to know about everything. What about occasional visitors to London? I think the few who use cash should be allowed to use it. And by the way, I know a lot of people old and young who still use cash at supermarkets and other / all shops. Indeed it is often quicker to do so. I shall always use cash, Oyster is useful and I would be happy to be able to use it to tap in and out for all things I buy, too. But please don't assume everyone's capable and socially aware of everything like some of you are.