Mo. Rev. Stat. § 150.540: Penalty for violations.

Every person who shall be found dealing as a peddler contrary to the provisions of sections 150.470 to 150.540 and as provided for in his license, or who shall, upon the demand of any sheriff, collector, constable, or any citizen householder of the county, refuse to produce such license and permit the same to be read, shall be deemed guilty of a misdemeanor, and, upon conviction thereof, shall be fined not less than ten nor more than one hundred dollars.