That's not quite true. It is used in colloquial speech fairly often. You could say: "Маш, поцелуй меня; Сань, дай закурить" instead of "Маша, поцелуй меня; Саня, дай закурить", which is formally "more grammatical".
Fair enough, but you wouldn't usually use it with anything other than a proper noun? Or would you?


Well, whether you believe the bottom of the ocean exists or not doesn't change the fact that it does.
I've heard some nonsense in my time, but really...are you serious? I know it's unfashionable to be faith-intolerant, but that sentence alone is an invitation to ridicule.