Le don spontané, psychologiquement bien plus gratifiant que l'impôt prélevé par la coercition :
"(...) donating money creates an even greater boost in brain reward centres than paying mandatory taxes.
Harbaugh explains this bigger boost has to do with the fact that voluntary donations are a personal choice: "You feel better because it was your agency that made the difference. Usually, when you are giving, people are watching," he says, which can be an ego boost. "