If I just maximize for cash earned, I need to compensate for other things. I want to maximize free time and minimize commute. I have errands to run and things to do. Having flexible work, with a work from home option is worth more to me than making more money. Otherwise, I need to spend more on an apartment close to the office. A more expensive car can make a commute more bearable. I value peace and quiet, and city living is at odds with this. Reconciling all this while working a 9-5 at a central office in the city costs a lot of money.
I currently work at 15Five, where "Embrace Freedom & Flexibility" is one of our core values. We actually are active in living this and our other core values. You can feel the effect directly. I have spent a lot of time thinking about this, and arrived at the same conclusion as this article.