Christmas and holidays in general are full of rituals that have been passed down for generations and only seem strange to modern sensibilities—like the punishments doled out by Krampus, a dark, devil-like counterpart to St. Nicholas. Some traditions are remnants of a time where the holiday season was more associated with the darkest part of the year and the cold of winter. Others are still developing: for example, in Gavle, Sweden, it's an accepted tradition to build a giant goat, but even though the goat is often burnt, that's not officially part of the riutal.
With all that in mind, consider the practice in Catalonia, in Spain, of beating a log until it "defecates" out presents and sweets. Atlas Obscura writes:
According to Catalan mythology, the Christmas Log brings small presents on Christmas (big presents come from the Three Wise Men) in the same way presents are placed under Christmas trees in United States. Originally, the Tió de Nadal was just a piece of dead wood, but now the log is often given a face with an attached nose and two little legs, along with a little red hat similar to a barretina.
The log is put out on December 8th, the Feast of the Immaculate Conception, and fed with nuts, dried fruit and water until Christmas or Christmas Eve. A blanket keeps the log warm. On that fateful day, kids grab sticks and beat the log while singing. There are a lot of different versions of the song, but they start with "Caga Tió," a command to the log to poop.
Here’s one family’s version:
The kids might reach under the blanket and take out gifts as they sing, or as in the video above all can be revealed with a flourish. Traditionally, the log was placed in a fireplace and after a "stinky herring" signaled the end of the gifts, it was burned. Oddity Central writes that the feeding before the beating makes the logs grow and that parents can keep the magic alive for their kids by replacing the log with successively larger ones.
It may seem strange if you’re hearing about the tradition for the first time, but then lots of other Christmas stories have origins obscured by time. And when you think about it, cutting down a tree, dragging it into the house and decorating it is also a little odd.