I didn't claim it was. But there is a big difference between "steal some plates from extended airport parking" and having to find and steal a plate specifically for the target vehicle. Obviously you could use the most common car and colour and make your task easier, but like for my SUV I see a similar colour / year / model on the roads maybe once a month. If I had to find another to steal or clone a plate it would legitimately be a pain.
this is one of those areas where the fraud becomes much easier with scale. if you are trying to steel 1 plate for 1 car, this is a problem, but if you're trying to steal plates for 1000 cars, 1200 plates will match 800 cars
Is it actually that much of a problem if you're trying to clone/steal one plate for one car? Go to some major stores with huge parking lots during busy times. Find one car which is the same model and color.
Maybe it's hard if you have a classic car with an unusual paint job. Not so hard if you have a white Toyota.
It doesn't need to be in bulk though. If you're not a dumb criminal looking to do this, you put in the work by just driving around a city center looking for a make/model/color you are interested.
Or, if you want to be organized, you run around with plate readers and log make/model/color/number and then sell that data.
