https://en.wikipedia.org/wiki/List_of_countries_by_milk_cons...
There was a research, which I can't be arsed to google with mobile, that compared western vegan diet and Indian omnivore and, yup you guessed it, the western version was less costly in terms of future proof.
But as with the zillionaires the human predicament depends on weather we muster the courage to limit ourselves or die to the extinction that's already manifesting itself in forms like forest fires, droughts and crop losses.