I think the term we want is "silver lining"

From The Bookseller (Italics mine):

Speaking at the keynote address at the London Book Fair this morning (22nd April), Boris Johnson [The mayor of London] enthused about the city’s many bookshops and libraries as well as publishers - and the English language itself. "Americans may be borrowing it, but we minted it," he said.

Drawing on the digital theme that carried through many of the fair’s seminars, Johnson, who has previously acted as shadow arts minister, said: "I don’t think Google is going to destroy publishing, I don’t think it will stop people reading books", explaining that as long as there were delays on public transport people would need books to read.

This explains much about the MBTA. They aren't horribly mismanaged, they are trying to help the local literacy rates!

Bonus Insight:

"I don’t think the internet is the threat it is supposed to be. I see only one threat, only one real challenge to the importance and attractiveness of books, one common foe," he added. "The Playstation."

The publishing world has hope there too! If everyone is stuck on the subway for hours, they can't get home to their playstations!