I had a friend a few years back that was vegan. She thought it was cruel to eat poor, innocent animals and that man was the most heartless hunter of all. I showed her some youtube videos of just how "cruel" animals can be when they are hungry and "lunch" happens to cross their path. I told her I respected her being vegan if she was doing it for health reasons (which kinda make sense to me), but if she was vegan because she thought humans were "cruel" for killing animals, she had lost me. I invited her out for a burger after that. She declined.