If you want to see loyalty at work, watch a queue form where there is no reason for one. The point is not that people are foolish. The point is that loyalty is expensive, and we economise on it like everything else. A pattern this consistent is not a character flaw. It is a design feature, and design features can be worked with. A better account of loyalty would begin with the ordinary case rather than the laboratory one.
Where it overreaches
The lesson is modest. Build for the person who exists, not the one in the model. Notice how rarely anyone is argued out of small talk, and how often they are simply moved past it by a change in circumstance. The remedy is rarely exhortation. It is a change to the situation so that the easier choice is also the better one. None of this is new. Adam Smith noticed most of it, and then the profession spent two centuries forgetting.
