I hope to see the day where interest bearing loans are recognized by the rest of the world as the evil they are. Muslims and Jews know this fact quite well.
>Jesus went into the temple courtyard and threw out everyone who was buying and selling there. He overturned the moneychangers’ tables and the chairs of those who sold pigeons. He told them, “Scripture says, ‘My house will be called a house of prayer,’ but you’re turning it into a gathering place for thieves!”
- Matthew 21:12-13
>If you lend money to my people—to any poor person among you—never act like a moneylender. Charge no interest.
- Exodus 22:25
KJV used the word "usurer", but it's the same idea.
i.e. when you are helping someone (a friend, relative) you don't pay interest. But when it's a business loaning the money that desire to help doesn't exist, and it becomes a business partnership instead.
https://en.wikipedia.org/wiki/Loans_and_interest_in_Judaism specifically: "Heter iska". And https://en.wikipedia.org/wiki/Murabaha for Muslims (I think there are other forms as well). A copy of a Heter Iska: http://www.jlaw.com/Forms/iska_d.html
Fees are one option. If you agree to a 2 year loan of 100$ as long as they pay you back 110$ that’s acceptable, the difference being if it takes them 3 years you still only get 110$. Obviously this runs into problems with inflation and people skipping payments etc, but it’s one socially “fair” way to handle loans between friends and family.
The Medici bank gained lots of their money from foreign exchange speculation issuing a sort of option for buying foreign currencies at a specific date (this would probably be a lot harder to do today), you could also charge late fees with the social understanding that paying a loan back on time is really bad for your credit score. I guess a modern conglomerate might make money by putting certain terms in effect: You want to build a house but need some money to do so? I will lend you the money if you contract my contractors to build your house. A university could lend you the money but keep charging extortionate tuitions as long as the cost for the education service is unregulated.
Almost impossible to imagine given the current state of the economy where every possible thing you can imagine has been commodified.
It is where the whole "Jews are greedy bankers" stereotype comes from: during the Middle Ages Jews were allowed to charge interest to non-Jews, so they were essentially the only people who could act as bankers for Christians. Combine that with a large dose of racism keeping them out of a lot of other jobs, and you end up with a lot of Jewish bankers.