Microsoft could make a deal with, say, Apple. They check each Microsoft Music (Xbox Music? Zune Music?) account for total spend, and give people an iTunes gift card for nearest total amount. Negotiate a bulk pricing deal with Apple.
Microsoft gets to look good, Apple gets to look good. But it'd cost 0.001% of total Microsoft profit and the shareholders can't have that.
Compare that to some other businesses that will happily recommend you to a competitor if it is a better fit, or if they shut down go out of their way to write a tool or help you with off- and onboarding to an alternative.
