Did you just "Ma'am" me?

Last night on the way home, way past the time I should be eating my dinner, I pulled through the neighborhood McDonald's for a chee-burger and a monstrous Diet Coke. Sometimes that's all that is acceptable, that Diet Coke. Anyway...I try to be friendly. Period. Maybe it's a girl thing, maybe it's a southern thing, maybe it's just good manners, but I've worked retail before, so I smile, I say "Please" and "Thank you" and I try to get along. Even when it's been a really long day. Even when the service makes a mockery of the "fast food" concept. I pretend that everything is hunky-dory. Really, even if it isn't, what can the dude at the cash window do about it? No need for him to suffer my day, too. I finally make it to the window and smile up at the large, pierced, tattooed man taking money. This seems like a better plan than the 12-year-old girl that I normally see, but that's not the point. The conversation goes something like this...

Me: watching him come to the window, I reach out with my money and smile (even in the face of the tattoos and rings. He's just a person, right?)
Him: Well, you're just all smiles tonight, aren't you?
Me: thinking furiously, what do I say to that? Thinking of my long day and how I would much rather have had this conversation about 3 hours earlier, I say...
Well. I guess I have to keep smiling no matter how late it is.
Him: Looks at me like I'm batty because 8:15 is probably not that late to him. He looks like he might be nocturnal.
He says...something I don't remember and hands me my change. And then he says...
"Thanks, sweetie. Have a good night."

Sweetie. I can't decide how that makes me feel.
But I think I might prefer it to "ma'am".

(And to my friends, this isn't him. This is a semi-famous tattooed person pretending to be an actor acting as a fast-food worker)