Regardless of the night you choose to hand out candy, just know the bulk of the trick-or-treaters will be coming to your door the evening of the 30th. You may want to turn out your porch light or be prepared to turn away dozens of kids that evening (unless the weather is ugly). Maybe you could place a sign on your door stating "I celebrate on the 31st". Parents will get the message. Not so sure the kids will. Although I know my candy bucket will be emptied on Saturday evening, I'll make sure I have candy for those kids who choose to trick-or-treat on Sunday. As far as the "LDS thing" goes, believe it or not, there are other religious communities outside of Utah that will be celebrating Halloween on the 30th. The 4th fell on a Sunday this year, it wasn't that big of a deal. The weekend actually felt longer.