Also, birthdays? Aren't those the sorts of things you find out about once per friend and then add to your own contacts? I've never had a Facebook account, but that's not a problem I've ever experienced.
Granted, I don't automatically know the birthday of every single person I meet or even get a number/email from. But I would go so far as to call that a feature, and because of that, the birthday notifications I do get are worth getting.