They defend the KKK's rights to free speech, not their abhorrent views. Protecting freedom of speech and the press is increasingly necessary in today's world, given how vocal Trump and his staffers are about shutting down dissenting views.
Also, I see that you are a new account. You should read up on the standards for discussion here on Hackernews.
You have a right to free speech, and these websites have a right to publish whatever they want. You are free to type things or to say things, there's no obligation for anyone else to host them or transmit them for you.
Also, I see that you are a new account. You should read up on the standards for discussion here on Hackernews.