Yes I'm with Freda, it does fit with sterotypes of rural and urban dwellers here in Australia too. There are subtle differences though. My True-love was born and raised in the American Midwest and before he opens his mouth his body language marks him as different out here in rural Australia.
I had a discussion with a folkie friend who had, like us, moved to the country and he was learning the index-finger wave and the slight head-nod. He reckoned he had it just about right, but it wasn't 'till he got the right sort of dog riding with him that men "waved" back.
I note that women tend to give a full on in-your-face wave to other women.