Why shouldn't they? They're getting paid loads of money. They're icons and heroes and they're there to spread the message that their company who pays them loads of money wants them to spread.
In the UK with soccer they had this issue, and then pointed out that players didn't have a problem with the advertising for betting companies (minus a few Muslims who refused to wear it) and other such large corporations.
You want to be a bigot, you can be a bigot, but you can do it on your own time, and you can quit your well paid job if you feel like your morals are bigger than your desire for loads of money.
How many quit? Zero? Oh, that tells you where their "morals" are at. Bigots.