Unfortunately, some people choose to be very cruel when they choose to conform to fit in with others.

"The rare images show Nazis singing, hunting, and even trimming a Christmas tree. They provide a chilling contrast to the photographs of thousands of Hungarian Jews deported to Auschwitz at the same time."

https://encyclopedia.ushmm.org/content/en/article/auschwitz-through-the-lens-of-the-ss-the-album