I hold Germany in such high regard when it comes to animal husbandry and the quality of its countless zoos, and so I'm surprised that the nation still has at least one "roadside menagerie". I would have guessed that Donnersberg was at least 50 years old, not just from 2016!
Every country has at least one sort of zoo family misfit.
Most likely unintended, but your "roadside menagerie" is a perfect description, because this zoo is literally situated in the corner of a large parking lot. From the outside it is more like a shabby garden center.