well actually most greeks do celebrate it on the 7th of january
Trust me here, you don't know what you're talking about.
actually i do cause i know people who are greek and related to me that celebrate christmas Day on the 7th of January and Christmas eve on the 6th of January which is 29th Kiakh
so don't you tell me i don't know what i am talking about because i do
“Several of the Orthodox Churches, however, did eventually agree, though not all at the same time, to adopt the New Calendar. These were the Churches of Constantinople, Alexandria, Antioch, Greece, Cyprus, Romania, Poland, and most recently, Bulgaria (1968)…The Orthodox Churches which have adopted the New Calendar observe Christmas with the other Churches of Christendom on December 25...”http://www.goarch.org/ourfaith/ourfaith7070
Whatever the particular customs or traditions of the Greeks that you know, the "official" position of GOARCH is to celebrate Christmas on Dec. 25, according to the New Calendar.