It supposedly highlights employees who have gone above and beyond, obviously setting up customer expectations that all McDonald's employees will be willing to, like, change their tire or something for basically minimum wage.
Anyway, there's another version of the missing tooth story where the employee not just gives a cup to hold the missing tooth, but a dollar! Out of their own pocket!
And you know the person who helped clear snow (why couldn't the driver do it?) got in trouble for leaving her post.