A registered vehicle is a licensed vehicle, and the proof of that is that the license plates are affixed to the outside of the vehicle as required by the vehicle code. The only way a city can tell if a vehicle is registered is by the plates because they can't readily search VIN numbers. Courts routinely uphold these laws and fine people who keep unlicensed vehicles on their premises. The key is that a car without plates cannot be driven and these codes were developed to prevent people from parking undriveable cars on their properties. Hope this helps clarify this code even if it's probably not the answer you were looking for.
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