Germans were surrendering in droves in the West, because they knew the Western allies would treat them decently. Only the most hardcore SS units were putting up any kind of resistance in the West after the Battle of the Bulge.
With the Russians, they heard the stories about the Red Army raping women, and they genuinely feared being occupied by the Russians, they had nothing to lose by fighting them.
Germans did most horrific crimes on the East, and they did them to Poles, Russians and Serbs.
Did you knew that 12 days after may 9th 1945, germans were still atempting to escape from Balkans? Two weeks after the end of the war.
they were horrified of prospect being captured by the Slavs