I grew up around this "shoot the dog if it isn't working out" mentality. Sure, it's faster if it's done right, but that doesn't mean I agree with it. I've seen people shoot their dogs because they simply didn't want them anymore. No other reason than laziness. I've seen dogs shot because they were going to be PTS anyway, and okay, fine, do that if it's what you need to do. But I have a hard time finding justification in shooting dead an animal because you no longer want the responsibility.
Growing up, my ACD was shot because it was sniffing around a chicken pen. Not herding or killing, literally just looking into it. He wasn't even standing up.
My step grandfather shot a setter in the head once, because she was too hard to find in the field and he was tired of looking for her. No joke. I've always thought that was a bullsh*t reason, just based on the type of man he was. But where I lived, that was the mentality. You don't want it? Kill it.
Maybe I'm too driven by sentiment to understand this philosophy, though. But yes, this story in the OP does **** me off.