If there was any question about John McRae's views on the use of alcohol, even the "moderate" use of alcohol, this poem makes the answer quite clear. 

It seems to me that since his brother Roderick and his sisters and their husbands lived close by, that the extended Mcrae family also adhered to the Temperence laws and refrained from the use of alcohol. This would include by own great-great-grandparents, James and Nancy (McRae) Fraser. 

When John moved his family to Liberal, Missouri in the fall of 1881, he was seeking a sprititual utopia in which to raise his children. The concept of the town of Liberal, as conceived by George H. Walser, was "...to build up a town that should should exclusively be the home of Infidels...a town that should have neither God, Hell, Church nor Saloon." Perhaps the use of alcohol was becomming more prevalent in Pictou County. While John McRae's rejection of traditional, organized religion is well established, perhaps John's desire to remove himself and his children from the spreading influence of alcohol consumption was as great a reason as any for leaving Pictou County?