Do all these games World Lore go out of there way to explain why there isn't a children's day? I'd assume regardless of World, there are children?

Maybe a Japan day is out of place in a world that has no Japan, but how far down the specific-line do you go before deciding to cut it out?

Christmas? Why couldn't many of the current MMORPG world's celebrate a day where they give gifts to each other. Maybe it's too contraversial to oust the "savior" and make it simply a day of gift giving so it can fit in the world lore?

Easter? All Easter was, was a the Christians taking the celebration of the goddes Estre(that people gave colored gourds to in her honor), and changed it around a litte to make an amalgam of the two religions.

Or is it simply the players perceptions. Does it destroy the "imaginary" world in their minds by introducing a real world holiday?

I guess personally I love it and want more. My reasoning is out of loneliness rather than anything else. I don't get to celebrate in real life due to work or distance from family and friends. So it's really nice to be able to celebrate it in-game, for me.