They are using 1st Amendment rights, and that's well and good as far as it goes.
However, they are not the only ones who can use 1st Amendment rights, and nowhere does the Constitution guarantee that any words or actions can't have consequences.
In other words, they are free to say what they want, and be free of government interference (for the most part) and retribution. But they are not insulated against private responses, or economic backlash.
Turnabout is fair game.