What would happen if you used your own blank plastic magnetic card? Would it be more durable? Would the vending machines refuse to load your fare onto them?
(I imagine the MTA doesn't have enough money for upkeep, let alone upgrading the turnstiles with NFC readers.)
The MTA has planned to upgrade to a tap-to-pay system in its 2015-2019 capital program, but that budget has a huge shortfall. Regardless, last I heard the metro cards are getting too costly to maintain so the rollout may still happen.
(I imagine the MTA doesn't have enough money for upkeep, let alone upgrading the turnstiles with NFC readers.)