Most men donate their sperm for free, why do most women sell their eggs?

Egg donors typically charge a minimum of 10,000 dollars for their eggs, which can be 8 or more eggs, and can only donate once every 60 days. Because of the high cost most people who want to be parents are going to fertility clinics and using donor sperm.<br><br>So why do most men donate their sperm for free? Men are just naturally more generous than women.