Airlines don't revenue share off interest paid by consumers. That's illegal. The credit card companies turn the exchange fees that retailers etc pay and give those to its card holders. Changes in these would require Congress to change the laws. Its unlikely. Also they did this in Australia and the airlines didn't get hit at all. They actually made even more revenue from card miles. First the airlines just issued their own cards to bypass this and then the card companies just gave less perks to card holders for things like sign up miles etc to make up for it. People in Congress benefit from these miles. They aren't going to change the laws, but even if they do the airlines won't care.