Each year on January 1, millions of Americans, having made New Year's resolutions to lose weight and get in shape, purchase annual gym memberships. A CNN survey indicates that 30% of all New Year's resolutions are abandoned by February 1; 80% by July. In other words, millions of people buy expensive gym memberships and then fail to use them. Does this indicate that these people are falling victim to the sunk cost fallacy? Or does it indicate that they understand the nature of sunk costs very well? Explain your answer.