There are double standards that harm our society, but it's not because they're double standards. I seriously doubt that most support for double standards come from pure idiocy or ignorance. There are two ways a double standard might exist:
In the first case, the hypocrisy could be an automatic reaction one makes, whenever one feels that something hold dear is threatened. A threat towards whatever you hold an emotional attachment to is perceived as a threat towards you. Most religious defences would fall into this category, as the religious person has such a strong bond to his/her faith, that (s)he overlooks all of the damages it has caused, even if people constantly point it out.
In the other cases, there might be a well thought out reason, as to why a double standard is supported. To give you an example, a possible reason for why men aren't as easily raped as women, is because it's much easier for guys to achieve an orgasm, while gals need to be in the right mood for this kind of thing. Now, one could argue the reason might be that females have a much more constrained and insecure sexuality than males, but that's another debate for another time.
Either way, pointing out a double standard and shouting 'HYPOCRITE', is not a legitimate method for silencing a certain stand point in a discussion. If you want people to step over to your opinion, you'll have to make it attractive to your intended target group.
