It's not really only $8/year. You need to also have Car-Net hotspot feature to access the streams. The internet radio terms say you need an active data plan, which according to Carnet support (when I spoke with them) means hotspot feature enabled. As a check, I paid for the $8 (annual rate) Internet radio feature during my first month when I had the free Verizon hotspot trial, even though I knew that it could stop working once the hotspot trial ended. Sure enough after 30 days it no longer worked. I can still access and see all the internet radio "stations", but when I try to connect to any of them the radio stream no longer plays. I have also tried this when my car was connected to my phone using my phone's hotspot connection. Still same result.
So if you want the Car-Net Internet Radio feature and you don't currently have Car-Net hotspot the annual cost is really $248 ($8 + 12*$20).
It's worth noting that Car-Net Nav Plus & Car-Net Speech Plus features that we get for free for 3 years also normally have terms that require an "active data plan" but they currently work even without hotspot. Who knows what the cost for Nav Plus & Speech Plus will be when our 3 free years are up.