Karaoke Revolution J-pop Rapidshare Why Does The PS2 Version Of Karaoke Revolution Party Cost So Much More Than The XBox/Nintendo Version?

Why does the PS2 version of Karaoke Revolution Party cost so much more than the XBox/Nintendo version? - karaoke revolution j-pop rapidshare

I was exhausted in the search for Karaoke Revolution Party for PS2 and regular "(in the main tent cduniverse said that he had been backordered since August 2007) and a turnover of between $ 60 - $ 120 and sellers in the Amazon. However, I found new for $ 10 for the Xbox and Nintendo GameCube, $ 20 with microphone. Why is it such a great price descrepency?