Who defines what “better” is? You’re a collection of atoms put together by a meaningless evolutionary process. In that sense, “better” is purely your preference not some objective truth. And in this case, some people prefer to kill and eat animals.
Or you know everything there is about infinity, other universes, how and where where "the playground" is placed (what's beyond its borders), what's the origin/meaning of life and so on?
Everything is meaningless and therefore we can do what we like? Even if it has no meaning to you, are you sure (deep down) it has no meaning for the lives you're taking (with your food choices)?