Most of the time, it is based on cognitive differences. First, China seldom uses plastic bags to pack money or documents. Second, China is accustomed to using m

Most of the time, it is based on cognitive differences. First, China seldom uses plastic bags to pack money or documents. Second, China is accustomed to using micro-mail or telephone instead of mailbox. Third, there are police stations or lost-and-found centers in public places in every region of China. It is too one-sided to rely on mail response rate.