It's way different to be on a train car with a bunch of strangers than it is to be in close quarters with one or two strangers. There's a reason that a cliche way to meet someone like an online date is in a public location and not, say, a car.

I'm also looking at it from my point of a view, as someone in their mid-30's. I'd assume the generations before mine will be much more likely to accept this than my generation.