I don't think it's something worthy of outrage.
It's a voucher for a food treat for active kids. It's up to us as parents to decide if and when to redeem said voucher.
McDonald's are donating big bucks to various organisations and charities - surely a little self promotion is to be expected?
What big company sponsors anything without expecting something in the way of advertising/promotion in return?
Don't like McDonald's? Then take a stand and choose a sport for your child that has zero funding or association with the fast food chain.