A hunter is a person who recognizes that he has a DUTY to do his uttermost to ensure a clean, quick kill. A clean, quick kill is paramount to a hunter. It is not something he hopes he will happen when he shoots an animal at long range. It something he has to be reasonably sure of, or he doesn't take the shot.
That's all very true. To put things in perspective, let me ask you this: are you reasonably sure of a kill shot when you shoot an animal at 50 yards? Are you less sure of a kill shot if the animal is at 150 yards? Has your confidence in a good shot at 150 yards fallen below your acceptable confidence threshold? I'm guessing you're sure enough about making a good shot at 150 yards that you'd take that shot just as readily as the shot at 50 yards. Well the same concept applies to hunters with a wide range of shooting skill. For some guys, shooting an animal at 300 versus 500 yards does not change the decision to shoot, as the confidence level is still above the threshold. Same with other shooters and shots at 500 versus 700 yards, etc. The important thing is not the distance, since that depends on the unique experience and shooting skill of the individual hunter, but rather what matters is, as you put it, a "clean, quick kill", that the hunter "has to be reasonably sure of, or he doesn't take the shot."
