In the discussion of free speech and the NFL, I’ve heard a lot of people complain about how the NFL does not support free speech because of the shoes or other apparel people have worn in the past. Things like 9-11 shoes, a decal on a helmet, eye black, or green cleats.
What people do not include in the conversation is reason why these athletes get fined for wearing non-sanctioned clothes. It has to do with contracts, collective bargaining agreements, and sponsors.
A lot of money goes into being a sponsor for the NFL and one of the perks of that is all of the athletes are required to wear authorized uniforms when they are representing the team. If Nike or the NFL looks the other way for one violation, then they will not be able to enforce the rules for other athletes.
The NFL does not want a lawsuit from a sponsor because someone wore the wrong cleats, when it is clearly written in the contract.