>If Burger King significantly increased the salary of their workers or otherwise found ways to improve their morale, would it benefit Burger King in the long run? I tend to suspect so, but it would be hard to prove.

It would not benefit Burger King as its clientele’s main goal is purchasing at the lowest price and they will happily go to McDonalds if prices went up. Not all businesses have the luxury of selling to people willing to spend more than rock bottom, and you can see that in most cities, only one or two areas where the upper middle class live will have the business that pay more than the minimum.