In Sweden for instance it's a bit in-between (unless the law has changed). You're allowed to film in public if you're using a non-stationary camera, but stationary cameras require a permit.

Yeah, Germany is different here. I am not 100% sure, but in Germany it is allowed if you are not focusing on any particular individual person. It is difficult to argue in absolute terms, which is why most consider public photos forbidden completely (unless for private/personal, very narrow use). Nowadays, in Germany, it has helped me to consider everything forbidden, unless it is explicitly allowed somewhere.

It's because of history. That's why Germany also resisted Google Street View initially.