I'm trolling a little Grunherz, but there is a bit of thought behind that simplistic statement. Indulge me for a moment.
Brutality was routine even when the going was good and they were winning. Just take a look at how they treated Russian civilians in 1941 during Barbarossa. I'd say that was a good measure of how far the poison of Nazism or at least the concept of race supremacy had seeped through the German armed forces. Their smug self-righteousness as they machine gunned refugee columns in France, obliterated towns and cities in Poland speak volumes, frankly. The 'bad apples in every bunch' maxim doesn't quite ring true; there's something more there, something appallingly routine and mundane about much of their conduct. While the Japanese were practically professional civilian abusers, the Germans were promising amateurs.
Now of course, there were honourable men in those ranks, good men, and it's sad they they have to be tarred with the same brush. They were unwilling spectators to it all, which is a terrible situation to be in. I'm sure it has been a burden to carry around all these years.
But having said this, the Nazi party was an insidious influence within the German armed forces; with all it's perverted agenda, this must have lead to higher proportion of people capable, willing and ready to commit acts of gross indecency against anyone deemed undesirable in the eyes of the Nazi leadership.
Oh yeah, the Russians acted disgracefully as well. No doubt about that. I've read Beevor's books about Berlin and Stalingrad. The Alliance with them came out expediency (like the Finland-German one, and that between the Swedish appeasers and the Germans). But the Western powers were always terrified of Red Europe as much as they were determined to prevent a Nazi Europe. Yalta was an effort to define an end to the hostilities, rather than having one war rolling into another. And that war would have been disastrous for the West.