Because some loonie union rep will claim that requiring employees to stand during the national anthem is a workplace rule or condition of employment that must be negotiated as part of the collective bargaining process, rather than unilaterally imposed by management.
Legally, the Cowboys probably couldn't cut a player who refuses to stand for the national anthem. But they sure as hell can bench the jerk right there on the spot, and then keep him on the roster but deactivate him for every game over the rest of the season. As long as they pay the player under the terms of his contract, the union has no grounds to file a grievance.
The NBA rules don’t allow it. In its rule book, the N.B.A. requires players, coaches and trainers to stand and line up in a dignified posture along the sidelines or on the foul line during the national anthem.
“workplace rule or condition of employment that must be negotiated as part of the collective bargaining process”
You’re likely right, with unions being what they are.
But I’d like to point out that the fans aren’t controlled by the union.
So all in all, if the fans drop out as they’re doing, and the NFL/players/union don’t wise up (due to the trickle-down rule being what it is) the NFL will soon lose money and the players will lose money.
And then the union will lose money - which is — IMO — the reason they exist.