Banks are businesses. Like other banks, they seek profit. What goods or services do banks offer customers? How do they earn profit?

Banks earn profit by charging interest. Banks offer loans, CD's and more. When you get a house loan, interest is charged which is how banks earn money. No bank has all of the money you give them readily available from everyone's savings account because they use your money to lend people which is why they pay you a small amount of interest for the money that you allow them to keep safe.