Marketing policy of McDonald's?
Answers: Make money.
As it should be, it's their responsibility to their shareholders. Of course, it can be argued that damaging the environment, contributing to our obesity epidemic and exploiting childish workers doesn't help make money contained by the long term. That's where things acquire a bit gray.
Make horribly unfunny commercials for the past 3 years. Except for the one with the guy who put the forks within the double quarter pounders and said "with cheese".