I can't speak to these specific events, though similar things are described in accounts like "Escape from Sobibor". These types of actions were extremely common, and were common before the death camps like Sobibor were built. They were used from the earliest days of the Nazi party, and were used throughout the Holocaust in various. They were purposely somewhat "juvenile" because these types of actions were particularly humiliating. Though on the surface they may seem juvenile or poorly planned most were very heavily orchestrated to specifically target their victims. Beatings were common, and usually public, it was also common to force Jews to clean the streets, sometimes with their own clothes or religious garments. Women were usually humiliated sexually, and were often raped. Many German soldiers photographed their victims before mass shootings, and usually forced the women to strip down to their underwear. These were often religious Jewish women who had never been seen by anyone but their husbands, sometimes they were young girls or old women, and they were always women who were terrified and about to be murdered. Religious men often had their beards and peyos (side locks) cut, often publicly, and were sometimes forced to take off their pants to show they were circumcised. The religion of Jews was often used to specifically humiliate Jews as Jews. These tactics were all ways to show power, to maintain control, and to instill fear. It was a way of making death, or living Hell, worse.