Wage gap: It is ILLEGAL to pay men more than women. Why aren't more women taking these cases to court?

Why do some women who are not as qualified or work as hard get paid as much if not more than someone that is working harder just because they are women? That happens more often then women being under paid. I am a woman but things like this make me mad because it is just giving unqualified women money because of their . For example, professional tennis player women used to get a lower prize winning money. They complained that they were under paid because they were women so Wimbledon decided to pay men and women the same. That would be fine if they even played the same amount of games but they DO NOT ! Men must play 5 sets and women only 3 sets. Where is the equality in that? Also, you do not see these cases because they do not happen as often as you feminist would like.