I get attached to my characters. Of course, I do that, too, but that's not my point. These games require commitment and reward it with a story, success, adventure and exploration. They allow you to befriend, manipulate, be nosy and get into things you would not otherwise have a chance to. There are about 100 examples that I could use to help this point along, but none that would do well for this family-oriented site.
Men like to feel.
Women like to think. I don't know. It just doesn't seem like a logical career path. If anything, I think the people who make the games are a reflection of the people who play them. So, it wouldn't surprise me if that same percentage applied on the other side of the fence.