How? I don't see it.
when a person becomes a vegetarian he used to eat meat, but not anymore.
you say he becomes better by becoming a vegetarian yet remaining equal with whoever still ate meat.
the person ate meat before, so he's both becoming better and not becoming better; becoming better by becoming vegetarian, and not being better because "it does not make you better than someone who eats meat".
are you understanding because i even confused myself trying to think of a good explanation