Annual earnings in the fast-food industry are well below the income needed for self-sufficiency, and fast-food industry jobs are also much less likely than other jobs to provide health benefits.

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.

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

Annual earnings in the fast-food industry are well below the income needed for self-sufficiency, and fast-food industry jobs are also much less likely than other jobs to provide health benefits.

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

When workers make more money, they respond by being more productive in their jobs and are less likely to leave, reducing turnover costs. This puts money in business' pockets, and workers also then have more money to spend in the local economy.

Most fast-food workers can't easily join a union, because they don't work directly for their parent company, such as McDonald's or Subway. Instead, they work for individual franchise owners, ensuring that each individual fast-food outlet would have to organize and win union recognition separately. So there's not one central employer to bargain with, as in a traditional union campaign.