These are strange yet promising times for the U.S. banking industry. Survey analysis performed for Packaged Facts' Unbanked and Underbanked Consumers in the U.S., 4th Edition report suggests a clear general trend away from having checking and savings accounts at traditional banking institutions even while consumers eschewing these accounts use banks for other products and services. This trend challenges the long-standing banking model that frames checking and savings accounts as the foundation for broader, deeper customer relationships.

Packaged Facts' research suggests that these "unbanked" consumers (those Packaged Facts defines as having neither a checking nor a savings account) include those who have been underserved or shut out of traditional banking channels for financial reasons.

However, a different type of "unbanked" consumer emerges: one who chooses not to have a checking or savings account at a bank because that consumer has more options, not fewer options; and one who may not even view these types of accounts as relevant in the 21st century. Many Millennials fit this description!

Survey analysis suggests a shift among Millennials toward account funding methods falling outside of traditional checking and savings accounts, in particularly emerging banking models. The trend clearly bodes ill for major banking institutions that do not adapt to the evolving needs of this group, which prize internet- and mobile-driven solutions, see "checking" as antiquated and irrelevant, and are likely savvy price shoppers, and are quite comfortable with online-only financial service models.

But Packaged Facts also found that younger unbanked have not forsaken traditional banking for financial services needs that fall outside of checking and savings accounts—far from it:

• In 2008, some 20% of unbanked 18-34s had nevertheless used a bank, a credit union or a savings & loan institution in the past 12 months for some other kind of product or service.

• In 2015, the percentage of unbanked 18-34s using these financial institutions for something else had risen to 37.5%. 

These activities could range from obtaining major loans to picking up a prepaid card, getting a money order or cashing in coins. The bottom line is that the theory that Millennials are abandoning banks may be significantly overblown: By one measure, traditional financial institutions are clearly bleeding younger checking and savings accountholders, but by another much broader measure, usage is on the rebound.

The question is whether that usage translates to major-ticket revenue in the form of major loans or investment vehicles, steady, incremental revenue in the form of credit cards and prepaid cards, or some other source—or merely an occasional piggyback on branch convenience for minor products or services.