In Finland the laws about keeping animals are the same, no matter what the animal is. So, you can't keep fishes in tanks that are too small for them, it would be like keeping a cat in a cardboard box for it's whole life. Or never letting a horse out.
No fish are allowed in a tank under 40 liters, 40 is the very minimum. Only snails and shrimps are accepted in nanos. Fish have to be kept in a tank which is both big enough and the water conditions are good for them. So, for example, keeping three goldfish in 100 liter tank is reaaally bad.
I don't find a strict laws about animal safety a bad thing at all!
That Romanian thingy sounds a bit odd. Yes, the fish could feel more safe, but if all of the walls are like that, it's not a good thing. It's recommended though that there was at least one wall in the aquarium where you can't see through. The most of us have one.