The government has to guarantee that there are places for people to say things. But the government does not have to guarantee that there are places for people to say things *in my own home*. And similarly, I think most public spaces should be free from ads and other 'attention pollution'. If a company wants to write about their own product, that's fine, but they must do so in a place where other people are free to seek them out, as opposed to doing so in a way that forces the writing upon others without consent.