Wrong, Allaha, wrong.  Team owners are the employers and set the rules which employees must follow while on the job.  Players happen to be the employees.  The First Amendment does not apply.   The rules should require all players to be on the field and standing at attention on the sideline without making and signs or gestures to support any cause or gripe to show respect for the National Anthem and for the fans who paid a lot of money to watch them play ball and not act like a-holes.