I will gladly concede the point that Sheppards decision was more right then wrong. There didn't seem to be another option at the time, besides possibly self-sacrifice. He himself could have went to the wraith posing as a villager and lured them to the cave. But since there were half a dozen men available who were frightened enough by the wraith to want to save their families by turning in some strangers they had just taken in, the situation could be resolved a different way.
Those guys weren't entirely true criminals, they were just scared people in a bad situation that the wraith put them in. I'm sure they had families and people they also wanted to protect. Even though they were naive enough to start turning the refugees over to the wraith, we still cannot possibly brand them as 'traitors'. If anything, they were more loyal then anyone, wanting to protect the village and people they've known all their life - families, friends - by any means necessary. What makes them unlike Sheppard, who simply chose to sacrifice a different group of people?
Without discrimination, Sheppard used them and put them in a situation where they would not possibly survive, a mine filled with C4. The action resulted in saving the lives of 600 people. But you also condemned people who didn't entirely deserve to die, despite some people here thinking they are outright traitors.