Why does the poet say, “I would not intrude on him”? Why doesn’t he offer him money to buy another ball?

The poet says, "I would not intrude on him" because he wants the little boy to experience the meaning of loss in life. He knows that his loss cannot be compensated by another ball. The poet does not offer him money to buy another ball because he wants to make him realize that nothing is permanent in this world and one has to accept the loss as a part of life and give up on things one loves in order to survive.