Debt collection is almost equally automated and anonymous. Price regulation is gone, too. California's usury laws can't be enforced against cards issued by Citibank from South Dakota. Banks charge 10 or 15 percentage points more to lend than it costs them to borrow. Credit cards, in short, have created a thriving new market for personal junk bonds.
Junk bonds cost consumers more to issue, of course.
When filing for bankruptcy is easy, there's no lower-grade security than a personal signature. Nobody with any sense issues a personal bond if he can float a secured loan for half the price. But some people lack security, while others lack sense. Working out in advance which is which costs lenders more than it's worth. So lenders send plastic to all, and set interest rates to allow for the inevitable mix of wheat and chaff.