Musicals are not inherently frivolous. Yes you could do a musical set in the camps if you do it with taste.
Well it was either at Treblinka or Sobibor they had an orchestra. It was a very popular one that toured Europe. Since they were Jewish they were put in the camp to play music as the people were being led to their deaths. Think of them as the Lester Lanin of Europe. So I guess you could do a musical about that.
"Miss Saigon" recreated the evacuation of Saigon, complete with a helicopter roof landing.
-PJ