Maybe I find a reason why to be vegan. Life is a give and take. We can say that if you live by the sword, you will die by it, so to speak. Or the hunter will be the hunted. So if you kill an eat an animal, your bound to be eaten yourself. If you take it to a metaphorical or spiritual level, you are being eaten by god or by life, whatever you call it. So if you don't want that, you got to stop killing in order to escape that realm of death and suffering. The first step is to not killing animals, the second is to not kill a plant and just eat fallen fruits or a little bit of nectar without killing the tree or plant. It would be the perfect symbiotic living.
You can have this goal, escape the food chain and go to another spiritual realm or remain in the food chain,( the humans being a superpredator int this system) and remain forever in this bloody realm. But as we are super predator, the turn of the wheel is ought to be violent. It's a choice that we can make and I think that in itself, the both are valid but we can't have both ways.