According to an article in Business Week, over 50% of fast food workers are enrolled in at least one public assistance program, a substantially higher proportion than any other industry. The low wages paid to these workers cost American taxpayers an average of $7 Billion a year. Is that really worth a Big Mac that’s a buck cheaper?
Here’s Barry Ritholtz writing on Bloomberg about this very topic, and how the existence of these public assistance programs act as subsidies to American businesses: http://www.bloomberg.com/news/2013-12-17/the-minimum-wage-and-mcdonald-s-welfare.html