(a) All agents of railroad and express companies doing business in this state are prohibited from charging, collecting, or receiving pay for any goods, wares, packages, merchandise, or any article whatever that may be sent or received by or through their respective offices in excess of the regular rates charged for those articles.
(b) Any person who violates the provisions of subsection (a) of this section shall be deemed guilty of a misdemeanor and upon conviction shall be fined in any sum not less than one hundred dollars ($100) nor more than five hundred dollars ($500).