The reason they don't want to leave Germany is Berlin is only place they can find people like themselves.

There is a reason Berlin is famous for leaving work at 6 pm on a Friday, going to a club, and exiting only at 4am next Monday to go back to work.

Not saying this is good/healthy thing, but Berlin has history of being the hotspot for misfits. That is why a lot of Germans or even Europeans move here.