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!