The true reason behind one's pursuit of wealth

A story is told of a wealthy man who would take walks every day to a lake to meditate. There he noticed a certain fisherman who would leave after capturing four fish only. This puzzled the wealthy man so much that he decided to approach the fisherman and ask him why he would leave after capturing four fish.
The fisherman explained that he would sell two of the fish and then take the other two as his meal then sleep the rest of the day.
"But why wouldn't you want to fish for more?" asked the wealthy man.
"Why should I?" asked the fisherman.
"So that you can sell more!"
"What for?"
"Then you can buy better fishing equipment, then fish more and sell more, meaning that you make more!"
"Why would I want to make more?" inquired a puzzled fisherman.
"So you can build a big house and retire in peace and rest!" exclaimed an exasperated wealthy man.
"But I already rest without having to do all that!"