Nah, Chase makes more money from charging credit card interest on balances than on interchange fees. It's something like 2-3 times as much as the interchange fees last time I checked. The interchange fees have very little consumer default risk and typically more than cover the marginal cost of issuing more credit cards.

Being scared of credit card interest is actually correct. It's just that it's a manageable risk through having the proper budgeting and financial habits. Take the fear, use it to make sure you could operate on a cash basis instead of credit if you had to, and then pay off every credit card statement on or before the due date.