拾金不昧该不该索要报酬？

Recently, an elder man in Wuhan goes to the bank to withdraw 3,000 yuan. The teller makes a mistake and gives him 30,000 yuan. The elder returns the extra money right away. However, when he tells his friend about it, many call him stupid for not asking for any reward. So the next day, the elder go to the bank again, demanding a reward. He gets a mug which is about 6.5 yuan. As a result, a good deed that is supposed to make both sides happy leads to an awkward ending. Whose fault is that? The bank's or the old man's?