Do you really need Facebook as a mediator to find out about stuff happening in your own neighborhood? We used to know where the raves were by the blank sheets of neon paper put up like fliers on the buildings they'd be held in. Posting on Facebook seems both unnecessary and boring.
Communication happens in the mediums available to people. You didn't have Facebook in those days, so people posted flyers. Now most people are on Facebook, so events are advertised there instead. You might see a posters for event sometimes, but I hear about local events through FB all the time. Particularly since friends of mine mark that they will attend or are interested, and they then appear in my feed. I agree with the argument that FB is just using us as their product, and that's not great. However, disregarding that, it's simply a useful tool to communicate with people! To avoid the shittiness, just unfollow the people who post tons of bullshit, and get some interesting friends.
Not saying my own neighborhood, I'm not tied in to every area between Portland and Seattle and since I can't physically be there at all times, I, you know, can't see those papers being put up? It gives me the option to go to a friend 45 minutes away and say yo, saw this thing, whaddya think?. Plus, the world's a piece of shit anyway so the fact that we're debating Facebook is egregious at best.