I deleted my account in 2005 when I noticed that it wasn't just for getting to know local groups. Before I deleted it I was contacted by a pretty woman who had 100 friends who were all the same last name as me. That's all she wanted to do is contact people who were "related". I had the suspicion she was a bot. People call me stupid for doing so, but now it is just bots?
There were some fun things like that back then. One of my early Facebook accounts was a videogame alias than included the work "clown", and I received invitations from other users that had "clown" in their names, its circle of friends became a virtual circus.