[morelisp]

I doubt anyone has been fined the full value just from killing one wasp from some random fine. It is regularly enforced against people who try to burn down or otherwise remove nests on their property (without engaging a professional to try to remove it safely for both parties).

I would say mainly it's not enforced because b) has been effective - Germans (or Berliners at least) don't kill wasps! If doing so became common, it would probably be enforced more consistently.