This is completely unscientific and based solely from amateur observation:
Women seem to initiate a lot of conversations with men who are known to be part of the woman's community, but not personally known to the woman. When a man is not known to be part of the community, the average women seems to avoid starting conversations.
By contrast, men seem to be willing to start conversations with any woman, regardless of kinship/having-been-introduced/community membership.
Theory: Women think in terms of social networks, kinship groups, best-friends-forever-clubs, etc., more than men do. Women *also* like to forage more than men do. They like looking at basically recognizable but individually unfamiliar things, and judging the qualities thereof.
And all of the above could well be completely wrong.