Folks,
Many thanks for the responses. In the time since my original post I have come across the following from the Missouri ATC: No Financial Interest in Retail Business - Distillers, wholesalers, winemakers, brewers or their employees, officers or agents, shall not, under any circumstances, directly or indirectly, have any financial interest in the retail business for sale of intoxicating liquors except a distiller whose manufacturing establishment is located within Missouri may apply for a license to sell intoxicating liquor by the drink in close proximity to the distillery. https://atc.dps.mo.gov/licensing/liquor_mfgr_solicitor.php
"Close proximity" is not clearly defined anywhere, though.