> They are extremely space-constrained Yeah and the amount of space is not really anything specific to the train. You can vary the amount of space in planes, b

> They are extremely space-constrained Yeah and the amount of space is not really anything specific to the train. You can vary the amount of space in planes, buses and cars as well, and the price will follow, just as in trains. There is no reason why space is "cheaper" in a train really, it's only the scheduling of few trips that make more space available, if you have more trips on the tracks, similar to a road, space becomes constrained, like you see in subway trains.