It does happen, security by obscurity is actually quite prevalent outside of Infosec: if nobody knows it's there how can it be stolen? Search for "Heathrow Run

It does happen, security by obscurity is actually quite prevalent outside of Infosec: if nobody knows it's there how can it be stolen? Search for "Heathrow Runway Robberies", etc. There were a number of documentaries on the subject, IIRC there were several gangs that specialized in jacking crap off planes in airports. It's possible (however unlikely) that some graduated beyond the airport.