Another reason, could be people who live in countries in which powermacs are not common (in spain for example, they are not very common). A powermac here, is around 150-200 eur (a dual 1.25). That same computer in germany or USA, could be around 70 eur. Shipping would be VERY expensive, as pmacs are very heavy. But shipping only the board and processor card, and assembling it locally in a ATX case, would be possible (and perhaps you could get a better price if you leave the tower aside).

[ Edited by amiades on 2010/11/17 21:40 ]