Because in reality, all friends and family totally live withing reasonable travel distance of each other and interesting people will always pop into your local

Because in reality, all friends and family totally live withing reasonable travel distance of each other and interesting people will always pop into your local bar at the exact time you're there and wear a shirt outlining why you should spend your time trying to meet them as opposed to literally anyone else in the bar. Email lists and chat servers are just Facebook with extra steps. The only difference ends up being the fact that Facebook-like social networks suggest you people and content you might like from a giant pool, whereas the alternatives have rather limited pools and the signal to noise ratio is pathetic because you get literally everything that is posted and have to filter through it manually. Don't get me wrong, I hate Facebook and only use it on maybe a handful of occasions per year, but you can't tell me that it didn't enable things that weren't possible for many before it was invented.