....so...as I remember the basic belief of Samhain...it is a time outside of the normal calender, basically a time that isn't recorded in the Celtic year, during which time people are allowed to step out of their normal societal restrictions.
Also during this time, the barrier between the worlds is thinner so that the fair folk and the dead can visit this world. What I've seen implies that this is seen as a chance to benefit from the wisdom of one's ancestors. Apparently the trick or treat thing comes from a decision to make sure to be polite to strangers on these nights because they could be your ancestor visiting you, in which case you don't want to offend them, or they could be fair folk visiting you...in which case you might be screwed either way, but you REALLY don't want to offend THEM.
So, I wonder if Samhain is a time when the secret societies confer with the ghosts of past members about circumstances in the world.
Would make a very interesting seasonal event.