The toughest part of being a woman is to move through obstacles and baracades to equal opportunity in employment. Even though more women graduate college more so than men, women still falls behind when it come to equal pay for equal work.
Most women are not vigilantes when it comes to fighting for equal pay. Most likely women accept the difference in pay structure unless they are willing to endure a job grievous that most likely would end up like the Walmart lawsuit.
I am not employed at Walmart but is aware of the class action suit that charged Walmart with not promoting women equally as men. The outcome of the Walmart case was that the court sided with Walmart because the lawyers said that the requirement was that each woman had to file a separate lawsuit.
In my particular situation, I am a government contractor but most often the men employees get the job because even though I have extensive government experience and a government clearance, the HR departments favor the men for the top notch government positions that requires a lot of traveling.