dogs' genetic programming has drifted so far away from true predators that the only real finishers are terriers, and they don't eat their killings. most dogs have been genetically manipulated out of the consuming what they kill in the service of using their skills of killing and grabbing prey to point, retrieve or tunnel in and kill various game animals and vermin. if they want to bitch about this, they'd better recognize that people are responsible for creating the problem and take rational steps to solve it.

the predatory sequence in these dogs might be missing the key parts of dissect and consume, meaning that the dog doesn't know what to do when they've killed something. see suzanne clothier's example of when her pyrenees was guarding a dead lamb: it's not because the pyr gave a shit about the dead animal, it's because she was guarding it as potential food that she couldn't figure out how to access because her dissect/consume sequence is not present. that's what people bred out of livestock guarding and herding dogs to make sure they wouldn't eat the livestock. border collies and other shepherds that actually go in to grab bite and kill bite livestock are usually culled from breeding programs.

predation is a natural part of the dog's behavior. it's not clear that they experience "fun" in hunting, they are doing it as part of their survival instinct. wolves don't hunt for fun. dogs don't hunt for fun. people hunt for fun. we can't put that assessment of the experience of the situation onto dogs.