While I also think women don't actually get paid less in general, when taking into consideration other factors, like hours worked (over lifetime), other rewards such as more emotionally gratifying jobs. Women an men are different we may in general look for different qualities in jobs. Is that such a bad thing?
All the surveys I have seen, seem to be look at the average wage of a male, compare it with females, and say oh no we have wage inequality.
But to play devils advocate it, maybe profitable to pay women less money and still hire more men, because women maybe willing to accept less for some physiological reason. (Women in general may be just be less pushy). You still have to hire people, and there is only a limited supply, it is skilled labor which may mean getting the right person may be more important to your bottom line than paying them a bit less. So out of 100 potential employees you pick the best, say 10% are women, assuming random skill level you hire 10% women. Then you negotiate in sexist manner either, consciously or unconsciously.
The simple fact is wages are not fair, they do not accurately reflect skill/effort put into it. If it did why do fund managers get paid millions when their funds under perform the market (basically you would expect trained monkeys to do better). I doubt they work harder than say a fruit pickers either. You may say they have more risk, but that is not really true either, say they loose all your money, as long as they didn't commit a crime while doing it, the worst that will happen is they will have to get normal paying job like the rest of us. If you want fair you are living in the wrong world.