"In some situation where you would be forced to something technically illegal you would have to let common sense and necessity help you decide the issue. If you got lost while skiing and were hypothermic and stumbled upon a vacation cabin, you may be faced with the choice between B&E and freezing to death. I think the choice is pretty obvious in that case, and I would hope the owner of the cabin would be understanding. Just as obviously one would expect you to pay for any damage and any items used (eg food, heating oil, etc)."

In "the good old days" (1950s) back country cabins -rancher's line cabins, ranger patrol cabins, and the like, were usually left unlocked, at least in Arizona. The understanding was you could take shelter and use the cabin if necessary. It was good manners to leave the cabin clean and stocked with kindling, etc. so that the next person could make fire relatively easily. The loaded Winchester 94, or equivalent, was stowed under the mattress in two cabins that we visited.

This all went away with the backpacking boom of the 60s.

I think I have pretty high moral values, but faced with starvation, especially of my family, I am sure I would do whatever it takes and accept the consequences.