When people just RSVP yes but they don't look at the event post, they don't bring what the need to bring, pay for their tickets, know where to carpool, etc. That creates a lot of wasted time and angry people who "missed the boat" so to speak. If there was any way to let the organizers choose whether or not people could RSVP from announcements or some way to FORCE members to at least look at the posts, it would be easier. Sometimes you can't explain an event in one sentence :)