At least here in Germany, that rarely happens. On a train, maybe, but not very likely. And as I said: you're never really far away from civilization in Germany. So if your are going to be stuck for hours, and you know it, you can always walk to the next village and back. Granted, if the weather forecast indicates snow, I take some blankets and a thermos or two with to drinks. But if you have to spend the night inside your car at temperatures below freezing, than your planning has gone wrong. Over here, there is always an alternative route, somehow.