As others have said some of us have 2 keys and the dash ignition uses the wiring from the collum ignition.
This is because the no1 safety feature from ADR point of view is that putting the steering lock on....must kill the power. If the dash ignition did not pass through the collum wirring then it would be possible to lock the steering whilst driving the vehicle
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It does not look the best but it makes the car mighty hard to steal.