I have people on my friends list who seem like they really dislike me. But I'm too lazy to go through it since it's no that important to me. I add everybody. I have nothing to hide, and it's pretty easy to just click add. I mean, if they REALLY wanna see the shit ton of posts I make, be my guest.
There are a few things I like about though. You can see who is online, so if you really want to ask a question or need some help, you can shoot them a message.
and if you're trying to keep updated on a thread that a friend posts on, you can just click on the thread straight from your wall.
So in short, it tosses more benefits your way than not having anybody on your friends lists.