Reason is biology/physics. You need ten times the biomass to create an equivalent biomass at a trophic level that is one higher. It HAS to be more inefficient t

Reason is biology/physics. You need ten times the biomass to create an equivalent biomass at a trophic level that is one higher. It HAS to be more inefficient to eat meat instead of crops because it raises your trophic level by 1. (Worst case is eating what were apex predators like e.g. tuna fish) About trophic levels: Level 1 are producers like plants. Herbivores are level 2, carnivores eating herbivores are level 3, carnivores eating carnivores are level 4 and then there's the apex predator that is not eaten by anything, usually. Some links: https://en.wikipedia.org/wiki/Trophic_level#Biomass_transfer_efficiency https://en.wikipedia.org/wiki/Trophic_level#Biomass_transfer... https://en.wikipedia.org/wiki/Ecological_efficiency#Ten_percent_law https://en.wikipedia.org/wiki/Ecological_efficiency#Ten_perc...