Because there isn't a lot of demand for English courses? Otherwise you'd expect them to increase prices and offer more English courses.
We can go even further - if Germany really offers anything close to an American standard of living and education you'd expect many people would learn German and go live there.
That's because the first undergraduate degree is completely free for all Germans.
> We can go even further - if Germany really offers anything close to an American standard of living and education you'd expect many people would learn German and go live there.
My entire point was, that European universities outside the UK and Switzerland are unable to compete with the US schools, because they are very unattractive options for foreign professors who don't speak the local language.
Even in Germany, probably 90% of the undergraduate courses are taught in German only. The percentage of postgraduate courses available in English is much higher, though. Still, most professors are required to be able to teach in the local language. Therefore, the number of international faculty members outside the UK and Switzerland is very limited.