Well, I guess that is one approach.
In some third world places, some people who are sick of bicycle thieves are setting out decoy bicycles, locked up like they are valued, and when the lock is cut, a safety is released, and when the thief jumps on to pedal away, a spring loaded pointy shaft in the seat post tube is triggered, and penetrates the bicycle seat and a couple inches of thief nether regions.
Not that I advocate such a thing, especially in an American city with hundreds or thousands of attorneys who may be in hot pursuit of ambulances and/or police who don’t like civilians defending their property.
BEN CRUMP TERRITORY