This is somewhat of a point of contention between a friend and I, who do you refer to as "hun" in your daily life? I have become more aware of who, and when I drop a "hun" as of recently. My own hun-habits include people my own age or younger, or specifically women who I deem as friendly, and close friends. But what if that close friend hates it, and finds it condescending, and even fake? It might even be argued that a certain demographic of bleeched hair, artificial nail, name brand purse wearing middle aged women who are the worst offenders of "hun-ing".
I say them all! Hun, love, dear, babe (in rare cases, lets be clear)...I don't even know when the habit started, but as proven by the above said friend, who points it out regularly, but at this point must even let the odd one slide, its a hard one to break.
Another big one I hear other people pet name dropping is "dear". And I'm sensitive to this one because my very own Grams despises it. She feels as though the user of "dear" on her implies she's a little old, incapable lady, which if you've ever met her, she certainly is not.
So listen to yourself, and watch for that subtle eye twitch from the dear you're hun-ing.