There is more productivity by having four coworkers sit together on a train and travel together than to have people in a car. Psychologically it’s easier for most to work on a train then a car, even if it’s a perfectly fine medium for you. Those time and financial costs are minimal when compared to the productivity you create by working together uninterrupted on the train.

If I were a manager I would ban driving and insist on trains (if the work would benefit from the added collaboration)