Disclaimer: I in no way support the Holocaust, i'm fairly sure nobody does. I don't like Hitler in any way, just always wondered this...
So the goal of the Holocaust was to get of people who were not of the Aryan, or German race, correct? It seems like they did it quite inefficiently. Couldn't they have just rounded up all the people they wanted dead and shot them on the spot? It seems like they kept people alive? Why is that? Why did anyone even survive?
They were often put to work in the camps, its not like they just sat around. Making clothes or ammunition was common. Many Jews were essentially slave labor, but many of the elderly or those too weak to work were quickly killed.
Efficiency seems to be the most accepted answer. While you might look at mass shootings as more efficient, there's really only so much you can do with that method. There actually are plenty of documented mass executions carried out by just shooting people. Prior to the final solution being agreed upon there were whole towns of people rounded up and shot in the beginnings of the Russian campaign.
Death camps ran like a factory assembly line. You could have a bunch of guards working all day shooting people and dragging the bodies off, but you can't really get through the amount of work needed to be done that way. When you're talking about the sheer numbers of people being killed in some places it just wasn't feasible to keep doing it.
It's also important to remember that outside of the most hardened Nazi supporters, these people were still capable of sympathy. Having soldiers shoot civilians all day is not good for moral. Having soldiers round up prisoners and load them onto a train separates them from the fate of those people. Even if they know the people are heading toward a death camp, they can remove themselves from blame because they weren't really the ones killing them.
This degree of separation was an important factor in the gas chambers as well. The people in charge of gassing didn't have to look their victims in the face while they did it. Even if the people in charge of gassing became depressed or decided they couldn't continue in their work, that's only 2 or 3 people at a time. That's much easier to deal with than an entire brigade becoming disillusioned after having to murder 5000 people.
So to boil it down. Death camps were more efficient than a firing squad because:
The partitioning of responsibilities was better for moral.
It took fewer men to kill more people.
there's always more room to explore this topic, but fyi, you can get started on some previous posts
Why did the Nazis keep Jews as prisoners instead of killing all of them immediately? - featuring /u/sepalg
I am German and I have some questions about concentration camps and the Holocaust. - /u/estherke
If Hitler wanted to kill all Jews, why didn't he kill them? - /u/estherke
Why Were Some Jews Kept Alive in Concentration Camps During the Holocaust?
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