London Transport’s pay-in-advance-then-go-as-you-please bus & tube ticket, available to people of any age, is called an Oyster card.
So all those who fret about having a free pass when they can well afford to pay, just because they are over 60, could salve their conscience by using an Oyster card whenever there is an R in the month.
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On not using one's bus pass
On not using one's bus pass