Yes, if it made it's way into the connection....(Curious)...Could this have been caused by spilling milk on the steering column, if some leaked in? (don't ask....)
Actually the ignition switch has nothing to do with the parking or head lights - unless you've modified the wiring.
You don't have to have the key in the switch to turn on or off. The lights are controlled by the switch on the steering column and you have to manually turn off the parking / head lights with that switch.