Two reasons.
1. They are made by a company that is owned by, or the liscence is owned by the company that makes the console (Killzone I think is a Sony liscence). Zelda is a fine version of this, with the N64 ones being made by nintendo, and the DS games made by Capcom for nintendo.
2. The company that makes the console gives a "lot" of $$$$ or other benifts to keep it on one console.
The reason they do this is to "win" the console war, and actually make some money on the investment they have put in (I dont think 2. actually helps, just look at the GTAIV DLC).
Bookmarks