PC Mark McKay, a police officer in Camberwell, London, tweeted this warning to locals to beware of bike racks that thieves have sawn through and camouflaged with gaffer tape; once the bikes are locked up, the thieves return, remove the tape, and make off with the bikes.
It's basically the principle at work in this magic gimmick, on a macro-scale.
Pls share and RT: Cyclist beware. We've had bikes stolen after being locked to sabotaged racks in #Camberwell pic.twitter.com/V4UHUEfvld
— PC Mark McKay (@MPSCamberwellGn) February 26, 2016