Many secular customs have become so commonplace that even the most faithful Catholics fail to recognize them as a slow ebbing away of the true meaning of Christmas.
In the traditional Roman calendar, this week, the third week of Advent, is an 'Ember Week,' and Wednesday, Friday, and Saturday are traditionally days called 'the Ember Days.'
There are multiple reasons for the mania, but they converge on one thing: the triumph of rational method and its (attempted) application to every domain of human life.