One should think of this as a form of asserting the failing national identity. By pointing out that you do not understand the rules, the locals affirm their sense of belonging. "Yes, I am a good German and bright enough to know that a yellow dustbin is intended for plastic only." Most of these rules tend to gravitate around weekend life, which is the times you will most probably spend admiring the countryside (and one is prone to spot the odd hordes of chappies either dressed to the nines or totally naked out in the forest).
The first rule to obey is something called "Ruhezeit", or quiet time. Anything from a crying baby to flushing the toilet may be considered an infringement. Be particularly aware of clauses in your rental contract which specify when you may be forgiven for flushing the loo. Loud noises should be avoided till 8 in the morning, and again around lunchtime. Following on from the confusing "everything is an exception" logic of their language, you may expect different interpretations of when exactly you should best take your lunchtime nap (without snoring of course).
If you intend to have friends over, and you consider listening to music, be sure to warn your neighbours (at least 4 houses deep in each direction) well in advance.
Most Americans are either shocked or ecstatic about German’s attitude towards alcohol. You can safely say that Germans do not consider beer an alcoholic beverage. You will encounter happy tipplers enjoying a brewsky on the train, walking down the street or sitting in the cinema at any time of the day or night. Well how could anything brewed