I think you're giving researchers too little credit in your first example. They do at least know that rational agents maximise expected utility, not just expect

I think you're giving researchers too little credit in your first example. They do at least know that rational agents maximise expected utility, not just expected money. And then whenever they do a study they are very careful to fully convince subjects that there is no trickery going on. And then when interviewed the subjects don't say "I suspected trickery". So I think that such studies are justified in concluding that the subjects are acting irrationally. >Our priors for "suspicious people offering bargains too good to be true are actually trying to cheat you somehow even if you don't know how" is very high. This is embedded in cultural/religious parables that teach "you do not make deals with clever demons," and because the culture that taught that has survived and persisted over time, it's probably a good prior to hold onto. Right, right. But the question of "why do people make irrational decisions?" is exactly what the researchers are studying. They agree with you! The answer is that decisions which are irrational in one domain would be rational in the domain we were designed for.