Let me first address Harvest vs Hunting. Hunting is a person out in the wild using skills and knowledge to take game. Harvesting is a person out in the wild using toys[rangfinders, super high tech stuff] to take game. The difference is one works very hard at being good, while the other is good because of his stuff. I can't afford stuff, so I rely on being good. Now to the ethics part, the problem is time. A lot of people just don't have the time to practice, so they rely on their stuff to get them their game. Is this ethical, yes if it makes for a clean kill. Is it hunting, no not in my opinion.
Gselkhunter