Unintended becomes intended

The curator is sad. One of his favourite examples of unintended use appears te be a forgery. A visitor wrote in the comments that the handcuffs pictured above are in fact sold as bicycle locks. At the same time, it shows us an interesting phenomenon: unintended use can become intended use. The production of handcuff-like bicycle locks must have started after someone unintendedly used real handcuffs as a bicycle lock. Who would that be?