There are way more PS2 models than Xbox models.
Since there are less Xbox models out there, the same modding / softmodding tools will work on most of 'em, unlike the PS2, which has many different models that blocked the modding / softmodding tools (no hard drive, removed bits on the motherboard, no support for booting off the memory card, etc.)
Also, I see people sell Xboxes with games in them down here all the time. The system is a pirate machine.