HALLOWEEN - A HOLIDAY?

Yesterday someone said to me , " Happy Halloween!" Now I'm sure that person meant well. But I couldn't help thinking, "When did Halloween become an actual holiday -one where we wish each other well?" Yes, yes, I know - great fun, costumes, trick-or-treating, fun and mischief the order of the day. But there's also celebration of fear, blood and gore, death, and evil. Ooooo great fun. But a holiday - a Holy day? I don't think so.

Lest you think I'm being too serious and picky about this, (I must admit that this isn't a huge deal) just think, we can "Happy Halloween" 'til the cows come home, but we can't say "Merry Christmas" because that's somehow politically incorrect.
What kind of sense is that?