I'm amazed that Christians have allowed Halloween to be a pagan celebration. Maybe that is why it is not an "official" holiday.
Most christian churches offer some sort of Halloween celebration. Seems totally contradictory to me, but then there I go again.
From the Satanic Bible, by Anton Szandor LaVey:
"Originally, All Hallows' Eve was one of the great fire festivals of Britain at the time of the Druids. In Scotland it was associated with the time when the spirits of the dead, the demons, witches, and sorcerers were usually active and propitious. Paradoxically, All Hallows' Eve was also a night when young people performed magical rituals to determine their future marriage partners. The youth of the villages carried on with much merry-making and sensual revelry, but the older people took great care to safeguard their homes from the evil spirits, witches, and demons who had exceptional power that night..."