Why did the allies demand reparations from Germany in WWI?
It was an expression of blame. Germany was to blame for the First World War (in the eyes of the victors), and should pay for the damages done because of its actions. It was common for European wars to end with reparations payments, after all. After the Second World War, the West learned its lesson, and rebuilt Germany rather than deliberately impoverish it, so as to provide a stable political and cultural situation where desperate people might again empower charismatic cult-like leaders. The Soviets, on the other hand, took reparations from Eastern Germany in the form of machine equipment, scientists, engineers, and all sorts of military resources and technology.
