By prohibiting interest bearing loans, loans become relegated to purely an act of charity, and as you point out, there will no longer be businesses that are bui

By prohibiting interest bearing loans, loans become relegated to purely an act of charity, and as you point out, there will no longer be businesses that are built only or mostly to lend money and profit off of usury. And that's a good thing. There's no reason why the car manufacturers won't be able to offer 0% interest on moderate term loans (a few years long). They already do today when they want to sell cars. This will drive prices down actually. You can also have longer term leases without interest, effectively paying for depreciation and the company can profit from leasing the car.