Rodo is right, the vast majority of pensioners have paid in for years and years; she is also right that not all pensioners need the free pass. What irks me is that those operating such things always go for the nuclear options to solve problems: do away with rather than modify.
The passes offer concessionary fares, therefore the fares do not have to be free. According to the LGA's own figures, that the grant has been reduced by £261m, the money could be recouped more than double if a charge of 25p was made for each journey. Nobody would have their bank broken for a 50p there-and-back journey and it would still allow the most desperate to get a free pass.