Recently, a bank was trying to decide what fee to charge for "expedited payments"-payments that the bank would transmit extra-speedily to enable customers to avoid late fees on cable TV bills, electric bills, and the like. To try to determine what fee customers were willing to pay for expedited payments, the bank conducted a survey. It was able to determine that many of the people surveyed already paid fees for expedited payment services that exceeded the maximum fees that they said they were willing to pay. How does the bank's finding relate to economists' traditional focus on what people do, rather than what they say they will do?