There is an important point missing. The bank can always lend for a better interest than it gives to its customers. In these cases, they lend for a negative int

There is an important point missing. The bank can always lend for a better interest than it gives to its customers. In these cases, they lend for a negative interest rate! Thus the customer pays 0% but the bank still makes money on the loan from for example a government bond of -1% that it is linked to.