Because I've played the crap out of all my Xbox 360 games, and it's boring.
My PS3 is so old and covered with dust. I don't want to break it.
My sister's Wii sucks.
The PS2 is broken, but I want to play DRIV3R again.
Yet for PC, you can do anything.
And you have thousands of games on demand.
Plus steam.
All in short, consoles are boring now.