Eugene Volokh highlights it:
If you hear that a woman wants sex but doesn’t have a partner, what do you think? She’s picky; she’s afraid of being emotionally hurt; she’s getting over a bad break-up; she doesn’t have the time for a serious commitment; she’s worried about pregnancy; she doesn’t want to be thought of as promiscuous.
If you hear that a man wants sex but doesn’t have a partner, what do you think? He can’t get a woman to sleep with him. A vast overgeneralization, of course, but it has some truth to it. Therefore, a male desire to use a vibrator is evidence that he’s sexually unsuccessful, in a way that doesn’t apply the same way to women. Hence, women with vibrator = sexy; man with vibrator = pathetic.
The Dish 