Ending life is not necessarily cruel...how about for veterinarians utilizing euthanasia? Let's say you have an animal that's 95% going to die sometime within 12-24 hours. If your client can pay $5000, which they can't usually, the chances improve to 50% chance of living. In most cases, for money or for suffering, euthanasia is the least cruel option, as it's vastly more affordable and a painless, harmless process.