I used to live in St. Augustine, FL...back in 1959.
There are many of us that have a key left in the saddelbag lock. But not the entire ignition key ring. We all do it with a custom knob on a shortened key, so it only opens the saddlebags, and will not work in the ignition. If done right, the knob looks like part of the bike, and unsuspecting hooligans would not know there is a key under that knob.