Tbh, I can't quite blame Punk for his frustrations. He's been working his butt off for almost ten years , and has yet to main event at WM (last match of the card I mean). The Rock did it TWICE ((although the WM28 match was to be "Once in a lifetime."), and now Batista's doing it again. This is a slap in the face to the full-time superstars and the fans.
I think Punk should have won and gone to face Bryan for the belt (Bryan could have won it at EC), and maybe turn CM Punk heel.. Would have been an amazing match, and fans would have been saisfied.
I consider him to be a bigger and better star than Dave Batista was, but alas Triple H seems to be living in the past, and pulls deaf ear on crowd demand.
That being said, walking out before WM is abig slap in the face for the fans. If he was physically burned out, he could have told talked about it on the RAW following the RR. I'm not blaming Punk, but ultimately the fans are the ones suffering for this.