It shall be unlawful to deliver any mail to any state mailing room, to be metered and dispatched, or to deposit in the United States mail any envelope, metered by a postage metering machine of the State of Nebraska, for any purpose or upon any business other than the dispatch of mail appertaining strictly to official business of the State of Nebraska. Any person violating this section shall be deemed guilty of a misdemeanor, and upon conviction thereof shall be punished by a fine of not less than twenty dollars nor more than one hundred dollars.