How do they make money?
* mortgage - using some billionaires account to buy housing properties and leasing them
* estate and lands with same patterns
* SMS alert charges
* Transfer charges
* Syphons dormant accounts or dead people accounts that are inactive with enough money in it.
* ATM and investment cards
* sales of currencies like dollar to naira
* preparation of international documents
* savings people's valuables like gold, certificate, court documents, WILLS, and so on.
This is what makes financial institutions very wealthy.
Banks are one of the oldest institution placed in charge of handling people's valuable properties & assets such as gold, money & documents for many years now, but apart from what you listed above, here are some other two important reasons how banks generate income, such as lending loans to people in need while charging high interest rates, and also using money deposited in fixed accounts for forex trading, shares and bonds so as the make more money.