Back in the Seventies and Eighties, the Russians were known to put explosives in toys, scatter them over Afghanistan hotspots, and let kids bring those toys back to their homes where they’d blow up.
Sometimes, their mujahedeen fathers and brothers would be at home, and the explosion would take them out.
Other times, it would just kill the kid out there in the field of rocks.
So when NATO troops thought to dress up as Santa and hand out gifts to the locals, yeah, that explains why they opened fire on them.
Thank goodness the Santa costume belly-padding was Kevlar.