no personal items to be displayed in their vehicles

Could this be to do with risk of theft of personal items and insurance claims - or is it a religious matter. Would it not be better to state that any personal items left or displayed in vehicles are there at the drivers own risk?

Article 9: Freedom of Thought, Conscience and Religion.

1. Everyone has the right to freedom of thought, conscience and religion; this right includes freedom to change his religion or belief and freedom, either alone or in community with others and in public or private, to manifest his religion or belief, in worship, teaching, practice and observance.

2. Freedom to manifest one?s religion or beliefs shall be subject only to such limitations as are prescribed by law and are necessary in a democratic society in the interests of public safety, for the protection of public order, health or morals, or for the protection of the rights and freedoms of others.

As far as I understand, a 'company policy' is not necessarily part of the law. Also one wonders about a cross affecting public safety, freedoms of others etc etc.