Germany has a long tradition of naturist culture, better known in other parts of the world as nudists. Cities like Rostock have beaches that are dedicated to the practice. Some are naturist-only while others are textile-only. There are reputedly beaches that are also "mixed use" which seems confusing to an outsider but the system appears to be working in Germany. For the most part, at least. Recent breaches in naturist beach etiquette have led to new rules being enforced.
The main issue is clothed people spending time on naturist-only beaches. This is considered a major faux pas and is actually against usage regulations. And there's a good reason for that. For naturist people using their beach, having non-practicing attendees hanging around makes them feel ogled and harassed, which probably isn't far from the truth. It seems odd that clothed beach goers would hang out on a naturist beach when there's dedicated space for them nearby.
Wearing clothes hasn't been the only breaches in etiquette at naturist-only beaches in recent months. Other issues include staring, making inappropriate comments, and even taking photos. The first two issues are definitely rude and would likely be considered harassment under German law. Taking unauthorized photos of naked people, regardless of where they are, is not only a breach of privacy but also highly illegal.
Beach wardens have been given increased powers in dealing with these situations to enforce the new regulations if a conflict arises. These moves are a direct result of issues on naturist-only beaches between nudists and clothed beach users. Problems have been increasing due to the decreasing prominence on naturists in German culture. Younger generations are not adopting the practice, leading to rapid declines in both the numbers of naturists and the services that cater to them.