It's not the cold here in East Central Wisconsin that keeps my bike in the garage...it's all the salt and sand on the roads. A few hours of riding are not worth the corrosion damage.
It is easily addressed with a quick wash before you put your you bike away. I usually hit the car was and rinse if off then put it back on the stand. The One thing I know about my BMW's.. They are meant to be ridden... Its ok to get it a little dirty..