Thanks to recent international treaties and safe-harbor regulations, they are forced to comply with DMCA. Even if a song is legal in Germany, if any of the parties involved (in this case, Warner Music) is in the US, US right, with DMCA, applies.

The US is quite literally forcing its laws on the rest of the world, and it gets worse every day.

This is also why so many are against TTIP. Trade treaty with China? No problem. With Japan? No problem. With the US? Fuck it.