But what would be so awful, I asked each of my informants, about a brief friendly chat with a fellow commuter? This was clearly regarded as an exceptionally stupid question. Obviously, the problem with actually speaking to a fellow commuter was that if you did it once, you might be expected to do it again — and again, and again: having acknowledged the person’s existence, you could not go back to pretending that they did not exist, and you could end up having to exchange polite words with them every day. You would almost certainly have nothing in common, so these conversations would be highly awkward and embarrassing. Or else you would have to find ways of avoiding the person — standing at the other end of the platform, for example, or hiding behind the coffee kiosk, and deliberately choosing a different compartment on the train, which would be rude and equally embarrassing. The whole thing would become a nightmare; it didn’t bear thinking about.
–Kate Fox, Watching the English