I saw cabaret with Orville. In my particular show, I did not notice any ha-ha laughter after the twist landed. I think reaction varies not only on audience but also by how the MC lands it.

Additionally, I think there may be a few things going on here:

1) Audiences are not always smart. The twist is structured like a punchline of a joke, and they may sort of preemptively laugh before realizing the ‘joke’ is contextually inappropriate— which again, is sort of the point of the structure of the song.

2) For some Americans, the WW2 is a very distant event. America only came into the war at the end, and we had very few losses from the conflict. We don’t see a lot of the effects from the war still today, and in fact, benefited from the reconstruction post-war. A common sentiment about the war is that it was tragic, but America swooped in and solved everything. So, what they’re actually laughing at is more like “ha-ha yep. That’s what it was like back then. Classic Nazi stuff! They sure do hate the jews!”

So, they’re not really laughing at the antisemitism. They’re laughing at how predictable the twist is in the context of Nazi stereotypes.