Goof: Troy is mistaken -- Jehovah's Witnesses may, in fact, consume alcoholic beverages, provided that they do so in moderation (i.e. drunkenness, the misuse of alcohol, is considered the sin -- 1 Corinthians 6:10). Members of the Church of Jesus Christ of Latter Day Saints (Mormons), however, abstain from drinking of alcoholic and/or hot beverages. Also, Jehovah's Witnesses do not believe in celebrating religious holidays (which Troy does in this episode, as well as Dia De Los Muertos a few episodes earlier). Another tenet is to limit friendship and contact with those who are not fellow members of the church (something Troy certainly does not do on this show).
All of these things put together suggest that Troy has either been "disfellowshipped" (their version of an excommunication), or simply doesn't know enough about his family's religion to know what beliefs to adhere to.