I might be wrong, but I think by far the bigger drop offs will be in the TV audience rather than stadium attendance. We might not see the impact of the players actions very much in stadium attendance.
Do you know how much it costs to attend a NFL football game? I took two of my boys about five years ago to see the Colts play. We sat in the nosebleed section, ate $10 per slice pizza etc. It was a $300 day, and they never asked to go back.
Think about a few weeks from now though when it becomes clear which teams are losers this season. I think in those markets, teams might find themselves looking at only 25 - 30 percent of capacity for their stadiums. Especially, when two losers play each other.
Maybe. I have seen a lot of ticket burning on social media