I have been thinking of a lot of incentivized networks and was almost coming to the same conclusion, that the extra cost and the questionable legality in certain jurisdictions may not be worth the payoff, and then the Nielsen scandal showed up on my newsfeed. I think there is a niche, just not sure where would it be most profitable. Incidentally Steve Waldman also had a recent post on this - social science data being maintained in a neutral blockchain.
About the shipping of products and placebos to people, I see a physical way of doing it, but it is definitely not scalable.
Let’s say there is a typical batch of identical products to be tested. They’ve been moved to the final inventory sub-inventory, but not yet to the staging area where they are to be shipped out. The people from the testing service arrive with a bunch of duplicate labels for the batch and the placebos and replace 1⁄2 the quantity with placebo. Now, only the testing service knows which item is placebo and which is product.
This requires 2 things from the system—the ability to trace individual products and the ability to print duplicate labels. the latter should be common except for places which might have some legal issues for continuous numbering. Ability to trace individual products is there in a lot of discrete mfg. but a whole lot of process manufacturing industries have only traceability by batch/lot.
Done. Foof that was long…