The fact that both T. P. and Benjy topple over makes it clear that what they’ve been drinking is somewhat stronger than standard sarsaparilla. The concealment of alcohol in a soft drink bottle was necessitated by the 1907 ban on manufacturing, selling and importing alcohol in Mississippi.
Prohibition had been spearheaded by a diverse range of interest groups. Doctors, women’s organizations, religious figures, white supremacists and beleaguered African Americans together constructed an overarching narrative that figured alcohol as a powerful enemy of the moral faculties; which, by gradually eroding the individual, spread crime and destruction through a whole community. So powerful was this rhetoric that in 1920 the entire United States adopted Prohibition through the Eighteenth Amendment to the Constitution. However, it ultimately caused greater social problems than it solved. Many citizens were unwilling to abide by its terms and the black market flourished, leading to a surge in smuggling, racketeering and associated violence. The countrywide ban was repealed in 1933. Mississippi, however, would remain dry until 1966, making it the last state to rescind.
Faulkner, an enthusiastic drinker, was vehemently opposed to Prohibition. When, in 1950, Oxford ministers began posting pro-dry posters around town, he responded with a leaflet now known as the 'beer broadside' — read it here.