So pull out sunroof fuse and see if radio still works

Of course they're necessary for something and you can't just get rid of them. The manufacturer wouldn't install them if they weren't needed. If you're looking at the large fuses under the hood, those feed multiple systems but there's only room to list the main things. Some of those fuses feed up to six smaller fuses inside the car and their circuits. Many circuits don't have a separate listing of their own in the fuse boxes. A perfect example of that is the radio. You'll find a fuse listed for the radio but not the second one for its memory circuit. That is tied in with the interior lights, and that's all that fuse is listed for.