Slaughtering animals for personal use by humans is not a necessary evil.
Unless you’re fighting for your life against an enemy, slaughter is a perversion. Even then, in a civilized world one shouldn’t need to fight for their life.
There’s nothing necessary that requires humans to continue down that destructive path in nature.
If you have killing urges, satisfying them by murdering and eating or wearing or hanging on your wall a defenseless animal is pathological. Sick – mentally deranged. Fix yourself.