Nobody, but our company delivers extremely niche health insurance market information exclusively to paid clients. Absolutely none of our clients are getting emails they didn't ask for and if their preferences change we have an extremely robust and granular interest system that we adjust to make sure they're getting everything they want the way they want.
It's a very different business from those assholes that require you to subscribe to their marketing bullshit to use their service though. In my personal life I've opted in to subscribing to about dozen things voluntarily... everything else gets spam marked.