I agree with you. But not only money makes born in rich families to earn more income. There is still a connection. They agree among themselves and where the ordinary person does not earn the money they earn millions.
Yeah even without taking into account the social aspect with education or things like that, the social groups are important!
It's so much easier to earn money when your dad is the boss of a big company...
You get everything you need. Internships, jobs, studies, formations...
It doesn't mean you didn't earn the money, it's just SO MUCH EASIER for you...