Let's face it, there will always be double standards.
Just the other day, I walked into "Lady Fitness" and tried to join, but they said it was only open to women; I left in frustration. I then went across the street to a hall where, over 25 years ago, I belonged to the Boy Scouts of Canada. I noticed the sign above the hall now reads "Scouts of Canada" as they now openly welcome females into the organization. The Boy Scouts was once a place for pre-adolescent boys to gossip about the opposite sex; that is now a thing of the past.
Whether it is gender, race or sexual orientation, there will always be groups which will exclude others; that is just the society in which we live. From my experience, an organization can get away with exluding any particular group, as long as you are not white, male and heterosexual.