Well... Commercial buildings often don't have a mechanism to remove the snow/water weight fast enough. They're nearly flat, much more square footage, and often have walls higher than the roof edges that slows down natural drainage.
I agree that the freeze/thaw cycles can be hard on the roofs. But, since I've lined nearly everything up there with Eternabond 10 years ago, I've not had any problems with snow. And we've had several 2014/15 Boston equivalent winters in that time. It's almost impossible to remove all the snow, and you can't do anything about the ice that's frozen into those areas you were mentioning except to heat the RV enough to allow it all to melt off. Of course I'm open to suggestions!