...why the hell can't they just play ball without all this patriotard crap?
One reason may be the fact that many consider American football to be a proxy for "soldiers", "warfare", etc, as this LA Times Article suggests:
Also, a lot of US football watchers are military vets, as well as many more active duty. By catering to this demographic, the NFL (NBA, MLB) can sell air-time to deep-pocket corporate advertisers. Money drives the sports mechanism in this country.