Back in August I commented on a paper by Mike Thicke that criticized prediction markets: With each of his reasons, Thicke compares prediction markets to some ideal of perfection, instead of to the actual current institutions it is intended to supplement.
The under-deterimination of theory by data, and a temptation toward post-hoc rationalization, can exist in all other institutions one might use to elicit explanations.
The difference is between a focus on giving reasons to others from one on making individual bets. [An individual 'talky collective' versus a market.] Scientists arguing about theories has proven a very effective way of securing agreement. Differences must be argued about; just collecting more data has never replaced scientific collectives. Yet that is the partial replacement you propose. Scientific arguments are not confined to the presentation of new data.