In Sports Economics one of the topics I talk about is salary of those in sports and one of the lectures focuses on differences in salary of men and women's NCAA basketball coaches based on research I have done with a former student of mine Sarah Foster. In that paper we look at how male and female coaches are paid and how coaches between men's and women's programs are paid.
What we know is that the salaries by program are much different: men's basketball coaches are paid more than women's basketball coaches. What Sarah and I did was investigate what drives the differences and what we found was primarily the differences in revenues between the two basketball programs.
Mirroring this idea is this article on the difference in compensation between men's and women's soccer here in the US in which the author offers the hypothesis that the reason that salaries are different is due to different amounts of demand by soccer consumers (whether in terms of quantity and/or price).