2. About the toilets that are never alone

Let's continue with the wonders of German's flats and after the moveable kitchen, the toilets. Yes, the toilets.

As a French, I am very used to have the toilets in a separate room, dedicated to this business. Except in a small studio, toilets are always on their own, even in those very old Parisian building with a weird layout.
How on earth can anyone consider hygienic and convenient to have the toilets next to the sink or the shower cabin? I think it is even more ridiculous for a household of 2 or more people.
I have read many articles about the reasons that explains why the Germans love their toilets in the bathroom and none make sense to me, especially since many Germans I met prefer separate toilets... Like the kitchen issue.
As the toilets are in the bathroom, it can be expected that closed cabinets would be fitted, but of course not. Like the kitchen, most bathrooms only offer a sink with no cabinet under, bathtube and shower (yes, usually both, which does not make sense, very useless), and the most improbable thing to put in a bathroom: toilet.

In many one-bedroom apartments I have seen, there is also a guest toilets, with a sink, so you usually have 2 toilets, 1 bathtube, 1 shower cabin, 2 sinks, all of this being a waste of space and more cleaning.