VERY Simple
$7.25 hour at the minimum. Which is the Federal Law. Mcdonalds pays more than that
McDonald's Hourly Pay | Glassdoor
Mcdonalds provides the job, they set the wages. IF you dont like it, you can go work somewhere else. They believe their workers deserve between $7.75 and 11/hr (hourly workers).
There you go.
Now, show me the data that shows they deserve an increase or a pay raise