The fan did nothing wrong. If you look at the photo there are other fans who are reaching out to catch the ball. They couldn't get close enough because he was in the way. If it wasn't him, then it would have been someone else. When was the last time fans backed away so a player could reach into the stands to catch a foul ball? Never has and never will.
Of course blaming the guy obviates ANY blame from Genius Dusty, Prior and Gonzalez et al. Multi-millionaire are never at fault. It's the paying public who screw up.