Even in purely secular terms, Christmas can still have substantial social benefits, as long as the people you celebrate it with are not pathological. Unfortunately, Christmas in my case does involve a very temporary reunion with blood relatives who I would prefer not to associate with, and therefore generally do not during the rest of the year.

At an atheists' special interest group I attended once, I got a round of applause from them, for suggesting that Christmas needed to be initially deconstructed and analysed, but that after that, if any genuinely socially beneficial elements to it were found, that they and they alone should be kept.