They used to use crosses too. Refinement takes time when you have 1700 years of embedded Christian/pagan mix to carve away. Christians faced constant refinement throughout the Greek scriptures did you think throwing off the iron tendrils of 1700 years of apostasy from trinitarians would be overnight?
You put false expectations on Witnesses.
The point is they were shown to be refineable from these false teachings and that includes the false pagan celebrations Christendom is so full of.
And being reformed from "Satanalia-mithras-winter solstice-commercialism-unreal Santa-Christ birth lie" Celebration was inevitable And happened quite quickly too considering how imbedded it had got.
The step from finding God's Biblical truths and principles and then applying them is a massive one as God's people and really showed the growing maturity of Jehovah's Witnesses
You want this false, commercial, sacred day that is so popular these days with all it's fakery now that you are no longer Witnesses?
It certainly reflects the step from truth to falseness very clearly!