How to understand Bobby Chen's saying that "you won't forget if you have money"

"Don't forget each other when you get rich" should mean "Don't forget each other when you get rich".

Interpretation: "If one day I (Bobby Chen) become rich, I will never forget you".

Source: Sima Qian's Historical Records Volume 48 Chen She Family Article 18

When Chen Sheng was a servant, he said to his companions, "If you have money, you will never forget each other. His companions laughed at him for not having such a fate. Later, Chen Sheng really became king, and the old man who worked with him remembered his unforgettable words and went to see him. Kill the old chap, "so there is no pro-Chen. "