From a writing point of view you are setting up a number of straw men just to knock them down. Carnivores (and we’re talking Humans here) mostly don’t kill their own meat. Vegetarians don’t want to eat future beings in eggs. Vegans kill animal life tilling soil. All may be true but they are not the absolute motivation of each group. So to use them as a given point to show how all three rationalize their choices is weak.
Does factory farming of animals create huge amounts of toxic materials and squander resources? Yes. Does mechanized farming of vegetables use massive amounts of toxic chemicals and harm animal life? Yes. These are facts, not straw men to prove a point.
Will either fact motivate people to change their eating habits? Some, but mostly no.
Humans rationalize ideals to make choices. All choices. That is what being Human is. We do fight each other about it, but I don’t recall anyone killing another over what they’re eating.
There are much bigger and more dangerous irrationalizations that cause war and deprevation and cruelty. It might be a better use of your talents to address those rather than berate people for making choices about their fuel intake.
A little about me
My choice of fuels: vegetables, fruits, grains, legumes and products derived from them.
I’ll even give you the reason: Its spirtual. I’m an atheist.
Physical: 6'2" 215lbs, healthy, muscular, active. Past middle age unless I live well beyond a century. My fuel choice suits me. And that’s a fact.