The argument the Watchtower Society takes could be applied to a wedding day, plenty of wedding material has the origen in the pagan world. Christians need to be aware of their intent, their heart condition along with their humanity. Have you meet a wicked person who abstain's from preceived pagan festivals while indulging in evil actions? I thought of different items accepted in our culture for a wedding day, why do they continue today?
The "wedding dress", "wedding ring", "wedding cake" have pagan origins we adopted into our culture, but nobody mentions these, except the "throwing of rice" which is highly frowned upon. Christians are not asking pagan gods for blessing on their wedding day, no fertility ritual (maybe learning about sex before hand would help men better understand their new bride and her wishes?) is performed to appease, invoke the diety to help a couple get pregnant. The intent and motive are what matter when worshiping and bringing honor to Jehovah and his Son Jesus Christ. Paul wrote in Collosians 2:16:
"herefore do not let anyone judge you by what you eat or drink, or with regard to a religious festival, a New Moon celebration or a Sabbath day."
I know the history of birthday cakes, candles, well wishes, gift giving, making a wish, astrological ("Horoscopes were of very early use in Egypt... and Cicero speaks of the Egyptians and Chaldees predicting... a man's destiny at his birth") We can go the route of ancient Jews who avoided this practice as well, the Jews had a bad reputation in Bible times for obeying Jehovah, their heart was heavy on perfunction and light on real issues Jehovah wanted his people to perform. There is too much to reconcile, people need to learn to read history, and decide from their learning, what a Christian is. According to first century historian Flavious Josephus, birthdays:
Nay, indeed, the law does not permit us to make festivals at the birth of our children, and thereby afford occasion of drinking to excess (Josephus. Translated by W. Whiston. Against Apion, Book II, Chapter 26. Extracted from Josephus Complete Works, Kregel Publications, Grand Rapids (MI), 14th printing, 1977, p. 632