I think this sort of thing reflects more than anything else the [necessarily] narrow 'excluded middle' approach of those collecting and analysing data. People 'believe' in all sorts of things that might lead to contradictions, because there is (to them) close to zero cost in believing in them, and because they are not as vested in proof and consistency. You could think of it as the old Pascal argument (might as well "believe" in god).
The inverse correlation between education (by which I am sure is implied formal education) and bible belief is explained naturally by the above, considering the fact that it is during the process of formal education that the criteria of consistency, proof etc in belief formation are emphasised, over other things.
--ravi