Your criticism is misplaced. PPP is not the issue, its the nonconstant marginal utility of money. If the marginal utility of money were constant, one would expect the results to be identical for a dollar or a million dollars, and billionaires would be expected to behave the same as day laborers. That is ludicrous. Rather than cultural ideas of fairness, the game more likely could serve as a proxy for the participants initial ex ante wealth endowment.
That being said, many of these 'experiments' in behavioral economics are silly, in that they capture so little of a real world environment and introduce substantial effects of their own as to be meaningless in terms of real (model driven, hypothesis building, testable, repeatable) science.
That being said, many of these 'experiments' in behavioral economics are silly, in that they capture so little of a real world environment and introduce substantial effects of their own as to be meaningless in terms of real (model driven, hypothesis building, testable, repeatable) science.