Are you saying that it’s never justified for anyone, including game wardens, to kill an animal in (what we judge to be) the best interests of the rest of the herd ?
Or are you saying that animals do sometimes need to be killed, but it’s not right to take a large amount of money from a rich first-worlder in return for letting them pull the trigger ?
For what it’s worth I personally think it’s pretty sick to get enjoyment out of killing. But as long as the method of killing is much the same whoever does it, and as long as it’s under the control of people who have the animals’ best interests at heart, then I don’t imagine that the giraffes would care much either way. The local rhinos might though, if the money could pay for wardens who would stop poachers from butchering them for their horns …