A poster posted this earlier and I think it deserves more attention because it is the reality of how a McDonald's operates.
A raise from $8 --> $10 is a 25% increase to total annual payroll expenses. An increase from $540,000 --> $675,000 or a difference of $135,000. Now, deduct $135,000 (change in payroll VC) from $153,900 (Net Income) and the franchisee makes a respectable $18,900 to pay his bills, and support his family.
This isn't magic. You can't make drastic changes to the McDonald's formula that has been operating the same way for decades. That's why it works. It is this way by design.