Trivia: Robert Duvall was asked to reprise his role as Tom Hagen, but an agreement couldn't be made on the price.
Trivia: In New York, Vincent is showing Mary the old olive company where Don Vito Corleone once worked and then owned. An elderly white-haired lady with a friend comes up and greets them, and tells Vincent about the troubles of the neighborhood. That lady is played by Catherine Scorsese, mother of Martin Scorsese.
Trivia: Talia Shire and Sofia Coppola, who play aunt and niece, are aunt and niece in real life.
Trivia: John Cazale appears as Fredo in archive footage from the other films. Although he was deceased by the time the film was released, he still maintained the distinction of having every film he appeared in earn an Academy Award nomination for Best Picture.
Answer: It shows you how greedy they are even as they've made it to the zenith of their criminal careers. That's why you see Michael pass it on disgustedly and stare blankly into the ether. Michael's goal was never to be the boss or capo di tutti capi, he only did it to protect his father and then his family, his main goal. And at that moment he realises he's never getting out. He's a business man in a world of criminals (which he is himself).