[marcus_holmes]

Berliners are renowned even in Germany for being blunt to the point of rudeness.

What we in the Anglosphere would consider rude, they consider efficient. It can be very off-putting at first, but you do get used to it.

[bryanrasmussen]

in most other countries renowned for being efficient it would not be considered efficient to answer in a language the questioner evidently does not speak.

[atoav]

To play the devils advocate: It is efficient — for them.

It is a bit of a myth that everybody in Germany talks English. Sure in an academic or business environment, or in certain social circles that can be taken for granted, but there are people who can only talk German or whose English is so bad they will avoid talking it.