So wanted gender equality, and yet so many double standards. I think women are (in U.S.) equal or even better postioned than men. Seriously, in civilised society as America, women practicaly just make up the problems so they could have something to complain about. Face it, we are different. Thats why we're attracted to each other. You cannot standardise everything because we are not standardised. We are physically different. Accept it, face it.
Still, to this day, many men are raised to think that they're superior to women. This way of thinking too often leads to them believing that they can act however they want towards women, often resulting in acts of violence, sexual harassment or rape. So when one of these men that were raised this wrong way now go to the gym, they will probably be confronted with a lot of sweating and maybe good-looking women doing all kinds of sports - and soon start to think with their dicks. This will now lead to them at least sexually harassing these women.
So the separate sections in gyms that are for women only are only needed because there are still too many men out there that see women as objects of lust or prey and think they're superior to them, often trying to violently (verbally or physically) force their will (sexual desires) on them - these sections are obviously for the security and wellbeing of the women, you see? And you would not want to have to pay extra for feeling safe in a gym if you were in their situation, would you? Because that would be gender oppression.