Long distance hikers, Ötzi from 5000 years ago ate large amounts of sheep fat and other high energy foods to stay alive in cold environments. It is important to understand how to render lard, as once you do it. The fat or fat back will stay shelf stable for a week or two in you pack... but its tasteless. You have to combine it with a protein and other foods. I am working on a Sloppy Joe idea here.
Be wise enough to walk away from the nonsense around you!