David Cain:

The ultimate tool for corporations to sustain a culture of this sort is to develop the 40-hour workweek as the normal lifestyle. Under these working conditions people have to build a life in the evenings and on weekends. This arrangement makes us naturally more inclined to spend heavily on entertainment and conveniences because our free time is so scarce.

Fascinating read, looking at how our lack of free time leads us to spend more freely.