Yes, banks have. Of course, they are not perfect. Some of them charge excessive (in the eyes of the consumer) fees or take risks with their depositors' money. But overall, they are certainly what we need.
The reason for this is twofold. On the one hand, people and businesses need secure places to keep their money and to be able to access it very easily. Banks fill this role by keeping our money and by making it easily available to us through checking accounts, electronic payments, ATMs and other means. Secondly, people and businesses need to be able to borrow money. Banks are an excellent mechanism for lending money to those who can use it in ways that will help our economy.