My mother died 7 years ago. If they offer me free food for calling my mother, I will break down in tears at the counter, become completely inconsolable, and then sue McDonalds for $50 million.
My mother would get a kick out of that.
If they offered me free food, I would promptly change my order to 10 of everything on the menu. I'd spend the next hour giving out free meals to everyone in the parking lot and drive-through. Imagine the effect that would have on their revenue!