"What's my favorite Christmas movie? Well, heh heh, actually, it's something you wouldn't expect. It's a little flick called..."
Die Hard is a good movie. A great movie, even! And yes, it takes place at Christmas time. But this madness needs to stop.
In the last few years, I've heard people refer to Die Hard as their favorite Christmas movie with increasing frequency. There's a certain smugness of sneaking by on a technicality: well, technically the movie takes place on Christmas Eve, so it counts as a Christmas movie. Most prized among people of this opinion is not a lifetime membership to the Alan Rickman fan club, but the transgressive act of selecting a violent action movie over Home Alone or more classic fare. We get it. You're too cool for regular Christmas movies. I imagine most people make the Tim Allen grunt after espousing this opinion.
But more than anything, I suspect that people think this opinion is unique. It's the betcha didn't see this answer coming that gives it it's oomph. You'll see this opinion trotted out by people who normally claim a psychical inability to pick a favorite film or album or artist. It is important to remember that not only is it wrong (Love Actually is the greatest Christmas movie starring Alan Rickman) but it is extremely commonly held.