It's a bad analogy. The rules of football are a set of conventions, and playing football (so, keeping to those conventions) is something people choose to do or not to do. So,

If you want to achieve the goal of increasing the well-being of humanity in general, and individuals in particular, then you should (in general) respect other people.

But what do you say to someone who doesn't want to "increase the well-being of humanity in general", other than him/herself? It's not as if you can go up to unsporty people and tell them "you [morally] should play football", if they've chosen not to.