vanHorck, you make the mistake of BELIEVING what you read. Non aviation people (and aviation people for that matter) may not be that skilled at calculating height over the ground. The public in that area are not used to see a relatively large airliner at "circuit height" over their houses. A B737-800 flying straight and level at a perfectly legal 1500-2000 feet may seem (to the eye) a lot lower than it actually is. Had the aircraft indeed strayed below minimum safe altitude you can rest assure that the authorities would have investigated the incident further.