Growing up with immigrant parents in the United States, I never really celebrated Halloween like most Americans. There were a couple of times when I got candy on Halloween, but those Halloweens mainly occurred from 5th grade to 8th grade. Before 5th grade, my parents probably didn't know that Halloween existed, and I thought Halloween was one of those school events. We also lived in an apartment, so we never had to worry about Trick-or-Treaters. After 8th grade, my parents forbade me from going Trick-or-Treating, because they thought I was too old. One of my high school classmates at the time went Trick-or-Treating, but he was actually denied candy, because the candy-giver said he was too old.
As I grew older, I became more and more acquainted with Western European Paganism and Christianity. The name, "Halloween," is derived from All Hallow's Eve on October 31, according to the Western or Gregorian Christian calendar. The purpose of All Hallow's Eve is to remember and honor the (Roman Catholic/Western Christian) saints. Lutherans are an unique group of Christians that also celebrate October 31 as Reformation Day, the day on which Martin Luther posted the 95 Theses. So, how in the world does this religious holiday get mingled with wicked paranormal activities?
Well, I opine that throughout history, many people were on the borderline religious end. They were sort of religious, because they were probably raised as Christians, and it stuck as a habit. They were sort of nonreligious, because they lived in the secular world (married/had kids/that kind of thing) without much thought about religion and all that spiritual stuff; and so old pagan customs got passed down. Over time, the name of the holiday is kept, but because of the number of borderline religious/nonreligious people, the customs are mostly pagan. With that kept in mind, it's no wonder that so many Christians reject Halloween. What they are really rejecting is the old pagan elements that got infused into All Hallow's Eve by borderline religious folks.
I believe that everybody should understand the history and purpose of All Hallow's Eve and the bastardized name, Halloween. Doing so may help people give appreciation to the subtle Christian and Western European Paganism influences in Western culture instead of dismissing religious influences altogether. Dismissing religion is tantamount to dismissing the humanities, as so much of religion talks about the human condition, good vs evil, and other cultural topics.