Mo. Rev. Stat. § 205.270
Every hospital established under sections 205.160 to 205.340 shall be for the benefit of the inhabitants of such county and of any person falling sick or being injured or maimed within its limits, but every such inhabitant or person who is not a pauper shall pay to such board of hospital trustees or such officer as it shall designate for such county public hospital, a reasonable compensation for occupancy, nursing, care, medicine, or attendants, according to the rules and regulations prescribed by said board, such hospital always being subject to such reasonable rules and regulations as said board may adopt in order to render the use of said hospital of the greatest benefit to the greatest number; and said board may exclude from the use of such hospital any and all inhabitants and persons who shall willfully violate such rules and regulations. And said board may extend the privileges and use of such hospital to persons residing outside of such county, upon such terms and conditions as said board may from time to time by its rules and regulations prescribe.
§ 205.270, RSMo