This paper explains why payment card companies charge consumers and merchants fees which are proportional to the transaction values instead of charging a fixed per-transaction fee. Our theory shows that, even in the absence of any cost considerations, card companies earn much higher profit when...

Anecdotally, a negative relationship between the use of debit cards and credit scores has been reported: Consumers with lower credit scores use debit cards more intensively than those with higher credit scores. However, it is not clear whether credit scores have real effects on consumer payment...