serious answer wrote:
Let's do the math.
There are approximately equal numbers of men and women. So are there more single men because there are more same-sex relationships among women, or because men who are in relationships often consider themselves single?
Well, it is probably true that men in relationships are also pursuing other partners on these types of sites but that may not account for all of the discrepancy.
It is probably also true that single men are more focused and proactive in finding another romantic partner then single women. Single women because of a whole host of reasons having to do w both biology and socilization, may be more content to be single and not proactively search for a romantic relationship.