Suggest a possible explanation using ideas from this course to explain the following phenomena. 'Data from 3 health clubs in the US shows that members who choose a contract with a monthly fee of $70 (allowing unlimited visits per month), attend on average 4.8 times per month. They paid a price per expected visit of more than $17, even though a $10-per-visit fee was also available. On average, these users forgo savings of $700 during their membership.