Humans are complex. You can either try to dig into the complexity and get stuck in the weeds of the individual with Psychology or make assumptions and build economic models that are at best 10,000 foot view of behavior trends with Economics. I accept that the models are oversimplified and at best are nudges on behavior rather than predictors of all behavior at all times. The economic models we have today are the worst models of broad human behavior except for every other previous model constructed. Ode to the Dismal Science.