Personally, my response to that is: "We can't live without harming anything else. I draw my line at plants, you draw your line at non-human animals, cannibals d

Personally, my response to that is: "We can't live without harming anything else. I draw my line at plants, you draw your line at non-human animals, cannibals draw their line at human animals. We have different philosophies and preferences". (And a Simpson's quote comes to mind: "Ha! I'm a level 5 vegan. I don't eat anything that casts a shadow")