I think different people find different uses. Sometimes it's a place to distract yourself in Random or games room.
Other times its useful to rant to a computer screen and have it reply. Sometimes you find that a particular person is able to help by suggesting something or sharing an experience. Sometimes that builds links between people. It's a very strange world to understand if you aren't in it I think, but actually real, strong helpful relationships can be built with people you've never met before....occasionally those people become more than that. I met my partner on the forum.
Sometimes it is helpful to just post stuff in response to other people. I think the point varies according to the person and the situation and whines online at the time