It would be free if done through a bank and you could actually get a lot of free steaks out of it. Once you have a little bit of money banks start treating you well, when you have a lot of bit of money they treat you really well.
His son--who only had single-digit millions--wanted to buy a house, so the dad talked to the bank and they arranged a zero-interest mortgage for him. They were happy to pass on what they might have earned from the mortgage interest (a few hundred thousand dollars, I'd guess) to make this guy a happy client.