Long-range hunting has its opposition, from both the outside and the hunting worlds. Because many hunters chose to follow Fair Chase ethics, they don't participate in long-range hunting. Fair Chase states that a hunter shouldn't have an unfair advantage over the animal he or she is hunting. The technology needed for long-range hunting is seen as an unfair advantage by many, giving this method an unethical reputation.
Most hunters aim for a clean, quick kill, but that means hitting the target prey in a very specific area. How are they to do this from several hundred yards away? Missing the small kill zone means that animal will suffer a slow, painful death or maybe not even die. And though a bad shot at close range allows the possibility to go after the animal and finish the job, tracking down an animal hundreds of yards away is impossible. In addition, a bullet to certain areas will only hurt the animal but allow it to continue living an impaired life.
As mentioned, there is a lot of technology needed for long-range hunting and it's believed that a majority of hunters don't fully understand the different variables [source: Zumbo]. In these cases, the risk of just injuring an animal is very high. An untrained hunter attempting long-range hunting can be compared to throwing a hail Mary pass in football.
While this method of hunting doesn't pack the moral punch of some controversial methods, there's certainly a strong argument for both sides. For now, we'll just have to see what conflict new technology brings us in the future.