Personally, even if the First Amendment were violated to shut them up, I would not care.
I am not a purist of the First Amendment.
It is my personal belief, formed through experience and my personal life, that excessive freedom breeds license. License to act as you wish without consequence is dangerous and that fosters nothing but maggots drawling about who slowly drain a society to death, and Europe...Europe sees this, hence why in certain countries, you could be arrested for saying things like what Westboro says.