I understand what you mean, but I suppose the 6 people had families of their own. Or, they could be 6 people in their 20s, just passing trough to see something they wanted to see. Looking at it from the f perspective works in both cases.
What I don't understand is how come such a meaningless decision (like to walk on the tracks) would be enough of a reason to justify their deaths instead of the workers. In other words, I am doudting the idea that their decision to walk on tracks was somehow wrong or false.
The way I see it, it's just an unfortunate situation. It's nobody's fault. Having said that, I don't consider the workers lives more important than the other peoples' lives. So it comes down to numbers. 6 vs 3. I just chose the lesser of two evils.