It's funny that in your examples you entirely chose excercise. The point is that it used to not be a choice. Most people were constantly socialising because th

It's funny that in your examples you entirely chose excercise. The point is that it used to not be a choice. Most people were constantly socialising because their work involved lots of socialising, and their housing was shared with lots of people. Those things are a lot less prevalent than they used to be. At school it's very easy to make friends not just because you're a kid or that you're choosing to socialise, but just by default you spend 6+ hours a day with the same people.