Well obviously I'm in a place where Christmas is just another day

But even growing up in the UK, we rarely bothered with a tree. There's absolutely no reason for it - does having a tree inside make you happy? Then buy one in May and keep it in your living room. It's a nonsense tradition that serves no purpose at all.
That said, I do like lights. I used to have my bedroom illuminated largely by touch lamps and UV lights illuminating balls I'd painted different colours. But that was year round, not just "It's Christmas so I must have some lights!"
I don't think of it as a curmudgeonly attitude, I'd just rather people thought about lights, plants and atmosphere year round, rather than just having to do it for Christmas.