Mo. Rev. Stat. § 572.100: Preemption — exclusions.

The general assembly by enacting this chapter intends to preempt any other regulation of the area covered by this chapter. No governmental subdivision or agency may enact or enforce a law that regulates or makes any conduct in the area covered by this chapter an offense, or the subject of a criminal or civil penalty or sanction of any kind. The term "gambling" , as used in this chapter, does not include licensed activities under sections 313.800 to 313.840.