Similar to this, my dad thought he was being smart by buying an $85 power cable with a keyed 'on-off' switch in it. The failing, however, was that we were very much a computer operating household and had dozens of regular power cables lying about. I switched a regular one in, left it there when I was done for my brother to use. Sometimes the keyed power cable would be back in place, and we'd just swap it out again. It was rather insultingly naive, and eventually it was thrown over the fence out back.