Whoa there! There's nothing in that report to say that the grumpy old fart followed any faith at all; why mention..
Ramadan, or Deepavali or Hanukkah or whatever your religion is based on, but Dec. 25th is the birthday of Jesus Christ,
It's got nothing to do with religion; for all you know, he had just lost his job and/or his wife, and had probably already suffered 148 occurrences on his way through the airport of some sparky young thing chirruping "Merry Christmas" at him because is/her employer told him/her to do just that, without any feeling or even eye contact.
I feel for this poor guy; by 1700 on 24th December I was ready to punch the next shop assistant, Muslim taxi-driver, Romanian street beggar, Big Issue seller, waitress, call centre operative, whatever, who muttered "Merry Christmas" at me without giving a gnat's fart about whether or not I was having a Merry Christmas, or was on the way to commit suicide as normal by 1700 on 24th December as I survey the commercialised, drunken hell that is Christmas bloody Eve in most European cities, to say nothing of Canada and the USA.
Scrooge had a point.