They (or anyone for that matter) can make billions if they learn the art of selling.
If so, most salesman would be billionaires ?
But salesmen are not the owner of the stuff they are selling. You should own the stuff (patent etc) and should be able to sell it to people.
Businessmen hire scientists and engineers, not the other way around.
They do when they become businessmen like Gates and Ellison.
I guess the question is really why is it that only businessmen make the bulk of money. Is sweet talking, managing, being social and creating hype really needed to make money even in this age of Internet.