Mo. Rev. Stat. § 311.330: Unauthorized liquors prohibited on premises licensed for sale by drink, exceptions.

It shall be unlawful for the holder of any license authorized by this chapter, for the sale of any intoxicating liquor at retail by the drink for consumption on the premises where sold, to keep or secrete, or to allow any other person to keep or secrete in or upon the premises described in such license, any intoxicating liquor, other than the kind of liquor expressly authorized to be sold by such license, or any kind of liquor used exclusively as an ingredient in any foods being prepared and sold on the premises.