Mike,
I think you are right that there are circumstances in which your estate might be protected depending on the structure of holdings.
That said, there is more general point of the moral obligation to ensure that third parties or passengers are properly protected from the consequences of our actions. I think I would feel pretty guilty if I caused an accident that led to an innocent person being badly injured. However I would feel a hell of a lot more guilty if they went uncompensated because I had saved a few quid on my insurance and then relied on a technicality to avoid my responsibilities.