((Edit: Snack, there totally WERE Halloween carols! Read on!))
Considering that Halloween can be considered a Christianity-rooted holiday, I always find these pamphlets funny.
All Hallow's Eve. The "Hallowed" being the Saints. Western Christian holiday honoring saints, martyrs, and the departed faithful. Trick-or-treating my very well descend from a practice called "souling", where people (usually children and the poor) would go door-to-door singing songs and saying prayers for the dead of that household. In return, they would be given little round cakes, called "soul cakes" or "harcakes". Each cake eaten signified the release of one soul from Purgatory. Bonfires were seen as purifying, and were burned to scare witches about their impending fate in Hell.
Was Halloween influenced by Samhain (pronounced "saw-in", fyi)? Oh, hell yes! But does it have Christian roots? Yup. ALL their holidays are mixed and/or stolen from pagan holidays, though. But they really like to pick on Halloween.