But NBC was the monopoly carrier of AFL games. If they didn't carry the AFL they would not have had any pro football.
I'll rephrase. As I remember, NBC decided their contractual obligation to air 'Heidi' trumped that of the AFL game in progress.
_That_ shows the respect the network had for the AFL. IIRC at the time they were two leagues with different contracts, and the NFL was king.
I bet Heidi was a crappy movie, too.