One of the terms used for the "crime" of hanging around with nothing to do is vagrancy. As the English Wikipedia entry puts it,
In legal terminology, a person with a source of income is not a vagrant, even if he/she is homeless.And what is the German equivalent of that? "Fahrendes Volk" according to the German Wikipedia. That definition applies to gypsies, but also to basically anyone -- or, more commonly, any group of people -- who are constantly on the road: acrobats, magicians, etc. Here, the stress is not on an income or lack thereof, but rather on the lack of a permanent address.
While there are certain fines related to such lifestyles (and the German entry does discuss crime), there is clearly no German tradition of charging people with petty crimes in order to get them on the wrong side of the law.
Another thing to like about Germany, though I must admit I fell back deeply in love with my country when we elected Obama.