I am not a big fan of the artificial tree or of Christmas. But Japanese love holidays, imported and national. I wonder whether the stations planned these small seasonal displays, or if they were the initiatives of long-time workers.
I prefer the use of the flowering “Christmas” cactus at the Shinjuku Odakyu station. And below the JR Metro Aoyama Itchome station’s faux snow tree in all its slightly adorned glory.