I don't think those are valid comparisons. And I running overnight buses can be much more expensive. Think about the ratio of passengers and energy per driver.

I don't think those are valid comparisons. And I running overnight buses can be much more expensive. Think about the ratio of passengers and energy per driver. And also, providing all night service adds to the value of working in the city. Knowing that I can stay at my office until 3AM makes living in NYC such a good value. And it also makes transportation something you don't have to think about; you just know it will be there. It would be really inconvenient if I had to wait until 5 or 6AM for the first morning train. I should have the option to get a train at 4:30AM if I want. Finally, NYC's subway is unique, and, for various reasons I mentioned in another post, would probably be more expensive to shut down at night.