I also think that Europeans have copied this rush from Americans.

Too much is being copied from there, I think the commerce is the most important reason ... companies pushing US traditions to increase sales. Haloween didn't use to be a Norwegian thing, now it's pretty big ... I've come to accept it, but then it's Black Friday, that has become a huge thing over only some few years now. I suppose thanksgiving is the next thing to be imported ...

But starting the Christmas push in November, that can be pretty well explained just through commercial pressure. The average European spend quite a lot of money on gifts, and the first shop to successfully nudge someone into buying the "right" present wins, hence it's always a race to be the first to remind people that the yule time is coming.