I put the seat up when I use it, I expect they can make the same effort to put it down when they use it.
-edit- Actually, it'd be less effort, as gravity reduces the amount of force needed.
My argument there is that you use the toilet seat in both it's up and down states. Females only use the down state. Asking us to touch the toilet seat when we have nothing to do with it being up is not polite.