These questions are becoming increasingly important as more businesses refuse to take cash in cities across the U.S. People without bank accounts are shut out from stores and restaurants that refuse to accept cash.

As it happens, a lot of people are still "unbanked": roughly 6 million in the U.S., the latest data shows, which is about the population of Wisconsin. And outside of the U.S., more than a billion people don't have a bank account.

I am a business school professor who researches society's transition from cash to electronic payments. I recently visited Seattle and was amazed by the mixed signals I saw in many storefronts. Numerous shops had one sign proudly proclaiming how welcoming and inclusive they were — next to another sign saying "No cash accepted." This tells people without bank accounts that they aren't welcome.

Why not have a bank account?

Why would someone want to avoid using banks? Every two years, the Federal Deposit Insurance Corporation surveys households about their connections to the banking system and asks people without bank accounts why they don't have one. People can respond with multiple answers. In 2021, the top reason — with over 40% of respondents choosing it — was that they didn't have enough money to meet the minimum balance.