My theory: Its Because the male warlocks have to wear robes to hide their boners while walking behing female hunters, While the female warlocks are sick of having to look at the male hunters junk while they hop around. Male hunters are tired of not being able to go invis and slap female warlocks on the ask without getting hit from 10 feet away, while the female hunters are sick of male warlocks following them all day asking them dum questions like "do you want to learn how to blink, because we can blink back to my place"