You ship me money, I ship you product. I don't need presence in your country, you don't need presence in mine. If your country doesn't like my product, they can enforce against you (or block it at the border).

I broadcast radio from my country, according to the rules of my country. If you tune in, and your country doesn't like it, they can enforce on you or broadcast something else on the same frequency if that's allowed by their rules.