Why do men believe women care that much about how much hair a man has?

Not to be shallow, but it is going to be anyways, because they do. Most women I know, love to tossle their man's hair. It is a sign of strength, and one of the qualities that the Greeks beleived deemed a man handsome. To a lot, it doesn't matter once you get to know them, but to others, a full head of hair is an added blessing.