I see a lot of mentions of GDPR in the comments, but the fact is that the sensitivity of personal information is an older mindset(not only a law) in Germany.

It is called "Datenschutz", and you see people proactively adhering to it, needed some time as a foreigner to get used to how rigorously they apply it, but when I got used to it, felt "safer" knowing whoever handles my data, knows how sensitive it is.

See https://de.wikipedia.org/wiki/Datenschutz for more information about the history.