Why did Frank break up with the steakhouse owner in the card room?

It was not Frank who broke up with his boss, but the boss himself refused Frank's help.

Although the black old man is tough on the surface, he knows Frank's friendship with him.

The main reason is that on the one hand, the black old man has become the weakness of his opponent's attack on Frank. Can he stop dragging Frank down by closing the shop?

On the other hand, the old black man was a gangster who killed people when he was young. He has been in prison and is satisfied with his present life. In this matter, he adopted an attitude of atonement.