I bought a huge amount of low cost DD games, but my favorite AAA games are on disc. Hey, I also rent films, and I'm addicted to netflix. But my favorite films are purchased in bluray.
But why only favorite AAA games on disc? i'd think that AAA games you want to keep would be better served on digital since you can play them on demand and you have no need to trade them in (since they're your favorite).
I understand Blu-rays, they're higher quality than anything you can download. I spent a few years building a home theater in my basement and theres noticeable difference in audio/video quality.