Woman Sick Of Men Spreading Legs In Subway Gets Revenge (6 pics)

it's not just the balls but also the way mens' hips are formed or the upper leg bone sits in the hip socket ... whatever these things are called.
You'll also notice that men usually suffer from O-legs, women more from X-legs, which is also related to that.

Our legs fall open "naturally" and it actually requires force to sit with your legs closed.

And you squish things you should not squish.