How much sports game viewership is just TV's with the game on for background chatter, or people watching the Superbowl for the half-time show? I think viewer rewards is something to take into consideration (I certainly used to idle in OWL twitch streams for free skins) but I think it's a bit disingenuous to claim all of them are untrustworthy.
The difference is that people will be talking about football well after the game is over. There is SportsCenter, there are the blogs, the social media....all of these things matter to advertisers, perhaps even more than the base metric of how many were watching the live broadcast.
