I find it rather curious waste of space, especially in ~50/60m2 apartments. Why do you need more than toilet and shower? I suppose that parallelized pooping and/or showering can be useful in rare occasions, but usually doing it serially works well enough and overall seems like an exceedingly poor trade-off. But the Brits seem to love 'em shrug.
Crossing borders can also be fun; with some crossings you can see an immediate and marked difference in building style; the Dutch/Belgian border is like that for example.
New Zealand houses are just horrible, full stop. Don't know how they managed to get so far behind on the rest of the Western world with that.
Not sure what I'm trying to say with this comment; don't really have a specific point as such. I just find it interesting that different countries have such different approaches to building and arranging houses, even though they're relatively similar in culture, climate, etc.