Tavella--I saw it differently than you. I think they tried to get our sympathy for Sawyer in showing him as a little boy, hearing his father murdering his mother and then cowering as his father killed himself. I think what they were hoping to do (and I don't think they quite succeeded) was have us feel some catharsis when he killed Not!Sawyer, and then take that away by in effect saying, "Now he's a murderer and all for nothing. He's even a failure in getting revenge." That didn't make me feel more sympathy for him. Pity maybe.
The writers went to a great deal of trouble to make Not!Sawyer sympathetic--giving him that nice cooking scene and making him confused and sad at death, rather than cursing or something. If they really wanted us no to care about his death, they could have done what drama commonly does, dehumanized him. They could have had Sawyer walk up to the cart and shoot him before he said a word and wasn't quite "real" to us.