Built Up Areas

[GulfStreamV]

Had a single engine aircraft (Pa28), fly over Surbiton (Surrey) (Heathrow Zone) today approx 1000-1500 ft (ish) - On a Northerly heading - How can this be justified?. If any of you know the area, there would be very few options in the event of an engine failure?
Just really surprised thats all!

GV

[FNG]

I was similarly surprised when driving through Hackney yesterday to see a Cessna single putterring over at no more than (I would say)1500 to 2000 feet. At this rate the Lea Valley lakes are going to be full of aeroplanes.