What happened to the joy?

When did it become fashionable to change traditional Christmas songs so that they now sound depressing or creepy? For that matter, when did they start making the main characters sound bitter (Rudolph, I'm looking at you), or make it seem like the song should be heard in a horror movie right before something bad happens? I mean, I can understand this new take working with certain songs that lend themselves to it, but not most of the ones I've heard lately.

(And when am I going to hear some of those scary ghost stories?)