Is it permissible to use the money generated from selling the customs exemption right for cars to returning emigrants in order to perform the Hajj pilgrimage?

Customs duties are not permissible except in very rare cases. Dealing with the right to exemption and taking compensation for it is not permissible because either the tax is legitimate, and therefore it is not permissible to circumvent it, or it is an unlawful toll that the state is not allowed to impose. Consequently, it is not permissible for someone who has been exempted from it to wrong others by taking compensation for a right in which they are legally equal.