I suspect that that's the point of the survey, though. Even though the questions can't be answered definitively, and even though they may really be the wrong questions to ask, we're faced with them on a daily basis.

Shakesville (http://shakespearessister.blogspot.com/) has a regular series where they point out how regularly various media outlets write stories about domestic abuse where the story is framed so that the victims (overwhelmingly women) are blamed for their assaults. This is an extreme case, but it's illustrative of how society at large (and each of us at small) doesn't approach blame in a reasoned and careful way that considers all the angles and second- or third-order causes.

I doubt the point of the survey is to actually determine blame for specific events, but to investigate how our faulty meat-brains tend to lay blame when we have limited information.