I was not impressed. Guy goes camping on the family estate and writes about it like its life or death and he can't just leave at any time to a posh life if he feels like it.
He didn't write "like it's life or death"! Most of the book are meditations on nature and descriptions of landscape. If that's what you came away with then you missed the point.
The part you remember was not about eating the animal due to hunger. He was observing that when he was away from "civilization" for long enough he noticed that he started to think in a more primal way. In that case, it was tearing a squirrel to shreds raw with his teeth! (or something) :)