So she drove the car home in an unroadworthy condition?. Ie half the number plate missing? and then parked up outside on the road. If the car is parked/used on the road then its commiting an offence. If the car was only lightly damaged and able to be driven then she should have gone and got a new plate. She is basically too tight to pay for a new plate thats what your saying. Some people do actually think the law doesnt apply to them.