compared to boys, girls are better at communication with people. So boys communicate with computer, but girls communicate with real people. And girls are afraid to become a "potato" sitting before the computer. aha......
I have seen many girls and womens whose working on internet and earning alot of money. I am sure you have never been visit freelancer.com
I dont agree to your point that Girls dont make money online i also know some girls on DP and others who are making great money by using basic technology and better communication skills