Another crazy thing I noticed when I came to Tennessee is everyone waves when you drive by them in the country. Someone could be mowing their lawn 100 yards away and when you drive by they wave. At first I had no idea why everyone did it and it freaked me out a little but now I find myself waving to everyone as I drive around. Just a lot of friendly people I guess.
My sister was in South Carolina recently and everyone there said hi and was very friendly. She tried to do the same when she returned to California and no one wanted to reciprocate.