Mo. Rev. Stat. § 8.740: Health and sanitation regulations, exception, guide dogs permitted.

The blind vendor of each vending facility is subject to the provisions of any ordinance or order of the city or county in which the facility is located relating to sanitation or health standards for such facility; except that, blind persons who are authorized to operate vending facilities under the provisions of sections 8.700 to 8.745 may keep their guide dogs with them on the property while operating the vending facilities.