Supposedly there's something psychological about a train. People who would never dream of riding a bus happily park their cars on the outskirts of town and hop a train to work. Stockbrokers can ponder their portfolios. Lawyers use the commute as billable time. Those guys don't miss a trick.
People treat a train with respect.
They may leave a newspaper behind on a bus, but they take it with them from the train. There's no eating, smoking, drinking or loud music. A few weeks ago, I had lunch with a judge in Houston who lives in the Medical Center area and works downtown. There's a bus that goes that same route. He just scrunched his nose.