IKEA is a special case for New Zealand, the story goes that NZ slighted IKEA in some way a long time ago, something like being unwilling to provide favorable zoning for a flagship store, and this resulted in IKEA leadership blacklisting NZ. This is often given as the reason that no store exists even today.
Quite possibly not true, more likely is that the small population and logistics complexity makes it uneconomical to service, especially for a brand that depends on scale.
IKEA-type shops were literally illegal in Ireland until recently (the law was changed in 2005 to allow limited types of shops, including IKEA, to have more than 6k sqm) and I don’t think they ever left us off their maps.
Europe got a really bad wrap in this picture. My guess is that it's the result of a bad automatic vectorization of a raster picture.
But I think that a missing NZ would stick out like a sore thumb to New Zealanders. Just like the Fennoscandian errors you mentioned sticks out to a Fennoscandian like me. It's intentional; no doubt.
It's a recreation of the game that Slack pivoted from. They also released most assets from the game into the public domain https://www.glitchthegame.com/
https://www.gouvernement.fr/gouvernement/le-systeme-d-inform...
They are simulating a meeting to define how to announce that the resource is gone! :)