The free market hasn't done a very good job "figuring out" how to pay workers enough. If it was solely up to the market, the people with the least power would be paid pennies ... or less.

Fast food also has a uniquely difficult business structure for workers to achieve better wages and working conditions.

The vast majority (over 80 percent) of fast-food and similar low wage service jobs (<$9.24/hr) are held by adults. A quarter are adults over 40. Another quarter are moms raising kids.

The minimum wage isn't earned only by people working at fast food restaurants and in service industry work - the average income for positions like nursing assistants, preschool teachers and paramedics are all under $15.

Income inequality and wage stagnation finally took their place among the principal moral issues of our time.

The fast-food industry is notorious for employing millions of Americans at poverty wages.

When families can afford the basics, they can reinvest in their communities, and higher wages means a broader consumer base for businesses.