2005 Toyota Prius Ethical

I took my car in due to a grinding from the front wheels. I was told that although the brake lining was adequate, there maybe was rust in the rotors causing the problem. I paid $220 for new brakes and there was no change in the grinding noise. I was then told that it was the bearings and they would have to be replaced. I have a warantee to pay for the bearings but not the brakes - do I still owe for the brakes? I did get new brakes but I didn't really need them as Prius brakes last a long long time. I'm OK with it either way I guess but I don't think they really investigated the problem before replacing the brakes the brakes.