Clearly enough people disagree for these TV channels to make the effort. And for the shops to stock all their Christmas ranges. Presumably plenty of people are buying.
Wouldn't do it myself, but each to their own :)
I've often gone out on the 1st December to get a tree. I think a real tree might look a bit sad and bald by Christmas Day though if I put it up in November, so that's not for me (also, it must make it a little bit less special if it's up for two...