According to their overworked website, Jehovah’s Witnesses in Germany now have „religious holidays (church holidays)“, such as the district conventions or “the holy act of baptism”:
http://www.jehovaszeugende.d235.de/Geschichte-und-Gegenwart.4.0.html
So, we should remember that “holidays that tend to exalt … a human organization are not in harmony with God’s will, and true Christians will not share in them.” (You Can Live Forever in Paradise on Earth, page 214) And “if there is a request for money … in connection with some religious holiday or celebration, Jehovah’s Witnesses would not contribute.” – School and Jehovah’s Witnesses, page 25.