Clearly your winters are mild, because you would know that even cleaning the camera before leaving does nothing, because driving for 10 minutes or more in the winter here is enough to completely cover the camera in crap, and making it useless...
This winter I also had access to a indoor parking at work, and my own garage at home. Even when leaving home with a clean camera, once arrived, when backing up, I had to keep a paper towel and go out of the car before backing up because the indoor parking was pretty tight, and the camera was completely blocked.
So I was actually having to clean the camera before I left home and before I backed up at work. just to be able to use it.
This is why in northern places such as I live in, having a camera hidden, unless going in reverse, makes much more sense. How its actually hidden (the solution/mecanism) could be different from VW as long as it works, It could be as simple as having a shutter type cover as found in some digital cameras... It just makes no sense to me to have a camera exposed 100%of the time when its being used maybe 2% of the overall driving time during its life.