Well, there's only one thing to be done then. I'll be waiting at Caesar's Palace; you bring the experimental funds.

Anyhow, the primary reason I disagree with you is that most people just don't expected to be cheated outright in psychology experiments; again and again it's found that the majority of subjects trust the experimenters.

Take for example the study on guilt where the volunteer signed up more often for a painful experiment if he thought he had broken an expensive machine, when in fact it was rigged to appear to break. You'd find different behavior if most of the subjects were suspicious at the outset.

I don't have primary literature with me now, so this is from the Wikipedia article

Allais asserted that, presented with the choice between 1A and 1B, most people would choose 1A, and presented with the choice between 2A and 2B, most people would choose 2B. This has been borne out in various studies involving hypothetical and small monetary payoffs, and recently with health outcomes.

You don't expect to be cheated in a hypothetical. You don't expect to be cheated by a doctor giving probabilities of different outcomes.

ETA: Here's an abstract, but the paper itself is gated.

ETA2: Paper!