I was a bit surpised as well. Ever since 07/08 depending on model all BMWs have heated mirrors. Prior to that it was part of a winter package.
Upside, there was a few other small things they fixed...got the bill...$0.00.
Maranello has treated me pretty well, when it comes to working on the car. I've always taken it to the dealer because I just don't need any hassles when it comes to CPO warranty work. Having said that, my CPO warranty runs out Feb 28, the car will need its InspI or InspII (I forget which) in a few months. Places like RPM or Stance Factory are like half the cost and money is money.
Life is like a sh!t sandwich...the more bread you've got, the less sh!t you have to eat.