Maybe it's the cultural divide, but I have always been put off by the cloyingly sweet friendliness of Southern women.
It gets my defences up- when someone I don't know very well is too friendly and nice, I start to wonder what they want from me. I'm more comfortable with a little bit more reserve when I"'m dealing with unfamiliar people."
I'll second that.
I grew up in Canada before I moved south to Michigan. I used to think that Midwesterners were too open and friendly, compared to Canadians.