There have been about 20 or so incidences of people dying and many more injured from CO poioning after forgetting to shut off their new, improved keyless vehicles causing, the cars to continue running in attached garages. I guess you could call that "unintended consequences". Pretty hard to do with old antique cars where you had to shut the engine off to remove the key...unless you are dead drunk. I guess we are creatures of habit, people relate taking the ID fob with them to taking the old fashioned key or key fob when they park the vehicle and don't realize the vehicle is still running? I don't know if I'm ready for a nanny car yet.......