Yep, I totally agree with you on that, Facebook is crap, but it's the brand, it's the most popular mainstream social network and it will take a lot of time and effort for every other network to get even close to it.
But.. just like Google they make billions from advertising and selling products to us, and we get nothing in return. Sooner or later people will start realising there are better places to hang around and get paid for doing things you do anyway all day long on FB.