I suppose you'd save a zebra from getting torn to pieces by a pack of hyenas? How is standing idly by in that situation any different? The hyenas could get their energy from grass just as the zebra did but naturally their lot in life was different via evolution.

You obviously think humans are born vegetarians but somehow tainted by the availability/taste of meat, and I beg to differ. I think humans genetics, just like lions or hyenas, had chosen long long ago that they prefer a mixed diet with meat. Show me where I'm wrong and how vegatarians/vegans don't have to take all those vitamin supplements just to stay at a normal weight and then I'll agree with you