No public utility shall give, grant or bestow upon any local, municipal or county official any discrimination, gratuity or free service.
Nothing herein shall prevent the entry into any public conveyance or in or upon the property of any public utility of any such official in the pursuit of his public duties in connection with the particular conveyance or property so entered by him, upon exhibiting his authority so to do.
N.J.S. § 48:3-6