> Most cattle is grass fed for the majority of it's life Nope. The majority of cattle industry has transitioned to factory farming and the cattle in factories

> Most cattle is grass fed for the majority of it's life Nope. The majority of cattle industry has transitioned to factory farming and the cattle in factories are fed with edible produce. Not grass. The current meat demand is not something that mere grazing can support. Even if it was possible to do with mere grazing, that's still not an argument: Grazing is done on land that could be used for many other purposes ranging from residential urbanization to vertical farming. Its not done in the Sahara desert or Siberian taiga where the land is actually not usable for anything else. Regarding byproducts: Such biological products are still valuable for many other purposes, leaving aside that many of them can be easily made edible through different processes. It again boils down to this: We are turning more food into less food. That's not a rational thing to do.