I personally have mixed feelings about this one. I get that many people are offended by seeing a fish ripped apart, and I know live feeding is problematic in several ways. At the same time (as I believe I mentioned before in this thread), I consider it rather cruel not to give live food to piscivorous fish. Hunters gotta hunt. Not just fish, either. It makes me sad when I go to a zoo and see the tigers and lions being fed dead meat. It isn't because I find great pleasure in seeing a goat ripped apart, but, as the movie said, “T-Rex doesn't want to be fed. He wants to hunt. Can't just suppress 65 million years of gut instinct.” (Dr. Alan Grant, Jurassic Park)
A hunter that isn't hunting is only half living, and certainly not demonstrating its natural behavior. Most people root for the antelope in the nature films. I love seeing a prey animal pull off a good escape, but I equally love seeing a hunter use its skills to put food on the proverbial table. It's a shame to treat them as if that part of their behavior doesn't exist.