Reading through the comments posted on the CBC's story, the reason why DW deploys such gross overstatement became clear: it provides cover for action. How so, you may ask?
Let's consider some alternatives. What if DW had said, "It's disgraceful. They should be fired over there." What if DW said, "It's disgraceful. They should be arrested over there." Or what if DW said, "It's disgraceful. They should be forced to meet everyone affected in person."
If you replace "shot" with "fired," then you would get political action. If you remove the hyperbole and make the threat realistic, then the story would be very different.
If DW said someone should get fired, then the public would expect that someone would get fired. But by saying that someone should be shot, he knew that the public would not expect that someone would get shot. He knew that it would attract attention to his emotion (anger) and deflect attention from his action (nothing).
In other words, he let himself off the hook. Like repetition, hyperbole has a specific political function to manipulate appearances and expectations.
I'm sure everyone has seen the story by now but, if not, here's the link. The public comments make for interesting reading: http://www.cbc.ca/canada/newfoundland-labrador/story/2009/04/06/cancer-count-eastern.html