I wonder if there'd be a difference between the survey as written (asking what a pen would do on the moon, and then offering a chance to change the answer based on Apollo astronauts) vs. a survey in which someone asked "Given that the Apollo astronauts walked on the moon, what do you think would have happened if they'd dropped a pen?"

The first method makes someone commit to a false theory, and then gives them information that challenges the theory. People could passively try to fit the astronaut datum into their current working theory, or they could actively view it as an outside attack on their position which they had to defend against. Maybe if the students had given people the information about the astronauts first, the respondents would have applied the cross-domain knowledge more successfully.

But I totally sympathize with you about the occasional virtues of compartmentalization. The worst field I've ever found for this is health and medicine. You learn that some vitamin is an antioxidant, then you learn that some disease is caused by oxidation, you make the natural assumption that the vitamin would help cure the disease, and then a study comes out saying there's no relationship at all.