If you look at McDonalds finances,(
https://www.google.com/finance?fstype=ii&q=nyse:mcd ) you will see they have a Selling/General/Admin. Expenses of approx $600 million each quarter, if you deduct the annual $988 Million they spent on advertising (
http://www.csmonitor.com/Business/T...-more-than-988-million-on-advertising-in-2013 ) you will be left with approx $300 million to salaries/employee benefits expenses. Now considering the majority of the employees make around the min wage, but not all would, you can safely assume that you could add another $200 million in expenses each quarter. Which means at the end of the year, the extra wage increase CONSERVATIVELY will cost McDonalds Corporation $800 Million a year.
And this is just for the Corporation, we haven't discussed most McDonalds
restaurants, which is much more labor intensive. The corporation doesn't own most of the restaurants, those are owned by franchisees, so I don't have the numbers on that, but I would assume that it would easily double their SGA expenses.
McDonalds is the second most successful fast food chain when it comes to margins (Chik-Fil -A is #1), and might be able to cope with a 25% reduction in profits. Many companies have margins that are much much lower, where an increase of wages would mean bankruptcy.