like the point is that is should be theirs?

But the “gains” weren’t really “theirs” either, since they previously belonged to an organism lower in the food chain. It’s the circle of life.

For the plants part, it’s worth mentioning that it takes more plants for animal products than it does to eat them directly

I’m not arguing for or against eating anything, I’m saying that no matter what you eat, you’re “getting their gains.”