To fair to them, it is illegal there.
I'm referring to filtering, by the way.
So too is keeping your engine running at railway level crossings.
One irate chap walked half a dozen car lengths to animatedly inform me of that one....how I laughed when the barrier raised mid rant and I rode away leaving him stepping back from the first lot of cars as they moved off after me.
My wife worked in Basel for a while and some of the rules where she had her flat were beyond belief if you’re used to living here. No washing machines or tumble dryers allowed in flats, no dishwashers allowed in flats, no flushing the toilet between 10pm and 6am and no showers between the same hours. There were plenty of other little gems and returning to traffic issues I was fined by Swiss police for parking my motorbike facing the wrong direction but at least it was a fixed penalty rather than a means tested fine.
I think different cantons have different regulations with the sensible option being to do what the locals are doing because it’s very rare that they’ll break the law
