Both retail and business banks are important to the US economy because they

Retail businesses are important because they provide millions of jobs in the United States. According to the most recent figures, almost 10 million Americans work in retail, from cashiers to store vendors, to low-level clerks.

Business banks are important because they provide much needed deposit services and credit to businesses and individuals. The modern economy would not work without banking, and this is why the banking sector is highly regulated by the government, and often rescued in times of economic crisis.