I'm annoyed at how often I have to explain this here.

I am not a government employee. I do not act as an agent of the government. Therefore, I do not have to respect your constitutional rights. If you harass me, I may take certain steps. The steps I take will be fully judged on whether my actions complied with the law. They would not be judged on whether you had the right to do what you did.

TSOs are employees of the government. When they are working, they act as agents of the government. When acting as an agent of the government, they are required to respect the constitutional rights of whoever is taking a certain action. They cannot deny constitutional freedoms by retaliating against individuals for exercising such freedoms.

Cohen v. California (the "F*** the draft" case) is a clear definition of the right to use speech such as this. You may not like it, you may think it's horrific, but it's protected by the first amendment. So you have to deal with it.