Is there a chance they stamp large sheets of cedar with something like that, then cut them up for box size, and your box just happened to be the one that had the stamp on it?
Couldn’t find anything. Only thing I can think of is it was within a limit of the first production boxes for that line for that factory for some odd reason and they had to do some kind of quality check. But that is a completely UN-educated and newbie-fresh guess.