Why would I take medical advice from my insurance company?

[Ron Obvious]

I've been getting a lot of calls lately from my Health Insurance company wanting to impart vital medical information to me. They leave messages imploring me to call them back to hear this vital information (though they don't say what it's about on voicemail, of course).

When I answered in person this morning, I told them I only take medical advice from my doctors, not from people who work for an insurance company that only wants to keep my costs down (and the premiums rolling in, presumably). This is self-evident to me, but they seemed rather offended.

I won't mention the name of my insurance company here, of course, but it's Regence Blue Shield if you're curious.

I don't get the whole US medical set up in the first place, but this was a new one to me. Is this commonplace nowadays?