Christmas celebration is not a matter of doctrine in any church that i have ever heard of.
There are many practices in churches that are not a matter of doctrine, but are indeed common practice. Seating in rows, pews, pulpits, baptistries, childrens church, sunday school, youth group, church camp, chiors, praise bands, pianos, organs, carpet, air conditioning, heating, electric lights, hymn books, sound systems, for that matter even personal Bibles. All these things fall in a catagory called niether commaned nor forbidden. But i know this will fall on deaf ears, so why bother? Maybe in the hopes of some soul may read it and not be conscience bound by unbiblical phariseeism.