He financed the pictures. On IMDB it says his is the only name to appear on all the sequels.
That means he's the money.
That's how rich guys get into the business. They agree to finance something, and then Hollywood lets them make a picture they want to do. People like Dodi Fayed and Ted Field did the same thing.
Was John Carpenter rich when he started in film? He has a long history of stunning film work.