At the recent Financial Literacy Education Commission (FLEC) meeting, one very enlightening presentation was by Barbara Ryan, lead researcher on the FDIC's most recent study of the unbanked and underbanked.  Here's the Executive Summary of the FDIC National Survey of Unbanked and Underbanked Households.

One surprising and dismaying finding: fully half the unbanked were previously banked, meaning they had decided that a bank account wasn't worth the cost or hassle. Moreover, more than half of the previously banked say they will not likely be banked in the future, either.

For too many, being unbanked is not a lack of opportunity to have an account, but an active choice NOT to have a bank account.  Banks are disenfranchising A LOT of people, and missing an enormous opportunity.