The MTA is thinking of having an off-peak fare, a discount for bus and subway riders in New York City. That's a good move - use the market and consumer choice to help solve the growing congestion problem on the roads and on public transit.
The problem with the discount is that it is being discussed in the context of higher subway and bus fares. The Straphangers Campaign would like to see less of the fare paid by riders and more by property-owners, and the late Professor Vickrey has argued that property-owners in NYC will benefit from cheaper public transit fares.
On the other hand, New Yorkers are paying one-fourth of the $8 fare on the London Tube for a single trip. The fare drops to $3 per trip in London if one buys an "Oyster" Card, which requires a one-time fee of $6. The structure of the fares appears to make tourists pay more.