On a packed commuter train, why do an obviously unhappy couple decide to start having a major argument with each other? From what they were saying it, it didn't actually seem like that much was going on, but they decided to air out all their dirty laundry in one go. I and the other commuters were just generally keeping our heads down as they kept on and on picking at each other until some elderly guy, I'm guessing from the US given the accent and logo on the baseball cap, told them that no-one wanted to hear their own personal domestic and could they stop spoiling everyone else's day. They kind of shut up at that point and slunk off at the next stop. Do some of these people not realise how loud they are and what impact they are having on everyone around?