London's Tube Is Getting 'Contactless' Payments. Could They Work in the U.S.?

In a conversation with Ryan Calo, a law professor at the University of Washington and privacy expert, he pointed out that if companies use information about how people ride public transportation against them, say to create a system of price discrimination so that coffee at Cosi is more expensive during the hours of the bleary-eyed commute, that would constitute a kind of harm to the consumer.