I feel like there is some real misunderstanding regarding paid, professional players (of any and all sports) and their right to protest. It is a matter of when and where. It is certainly their right but not when they are on the clock. Just like a MacDonald's employee could not expect to be paid if they sat out front of the store during his shift and held a protest sign.
One sign at a Kansas City Chiefs/Washington Redskins game said, "Protest on your own time". That summed up nicely the crux of the matter in my mind.