It's a sin for good reason, and the secular case against usury is just as strong. It's among the worst manifestations of rent-seeking, economically worthless behavior for anyone but the usurer.

This kind of lending is economic slavery. Why should a credit card company get a 15-30% return on their investment each year? How about 400%? You can use whatever clinical microeconomic language you want about risk and investment principles and rational actors and etc etc, but people now depend on credit for their basic needs. Then lenders can petition the government to garnish borrower's wages and gain eternal, guaranteed payment often on just interest. The borrower works and pays forever without even reducing the principal, and butts sit in offices redistributing wealth to themselves without adding any value to society.

It should be illegal to charge that kind of interest "investing" in the basic needs of people. The absurd prices of basic necessities in America now demand mortgages, car loans, student loans, medical debt, and credit card debt just to squeak by as a normal middle class person. Debt wasn't the solution to the price problem, but rather the cause.