The average debt load among credit-card-indebted households is more than $8,000. This figure might have you imagining financially irresponsible people charging for new sofas every two years and buying $3,000 television sets when their rent is overdue. Sure, these folks exist, and shame on them. But not everyone saddled with credit card debt is made of deadbeat fiber.

According to an article by Stephanie Salter at, those who are racking up debt are increasingly doing so by charging essentials, such as food, necessary car repairs, healthcare expenses, and schooling: "According to a riveting study by a pair of national not-for-profit, nonpartisan organizations [Demos and the Center for Responsible Lending], about one-third of all U.S. households categorized as low-income or middle-income are racking up credit card debt to pay for basic living expenses."

The report notes: "What distinguishes low- and middle-income households with relatively high levels of credit card debt from those with lower levels of debt is chance and misfortune." To understand just how close to danger many people are living, Salter points out that while wages of lower- and middle-class Americans have risen merely 5% (inflation-adjusted) over the past 20 years, life's fixed costs (housing, child care, health insurance and taxes) have jumped to represent 75% of annual income, up from 53%, over the same period.

Predatory lending hasn't helped the picture, as credit card issuers make life more difficult for borrowers. (Do you realize that if you're late with a payment for one credit card -- or even a utility bill -- other credit cards may hike your interest rate?) Companies accused of predatory lending include Citigroup (NYSE:C), Wells Fargo (NYSE:WFC), JPMorganChase (NYSE:JPM), and Washington Mutual (NYSE:WM), among others. To learn more, type one of their names into Google along with the words "predatory lending."

It's also alarming that many people have refinanced their mortgages in order to pay off high credit card debt, only to find themselves back in the hole in a big way just a few years later. They may have bought themselves more time, but they probably lost a significant chunk of their home's equity in the process, a potentially disastrous move.

Whether you're a credit card user living on the edge or an investor interested in banks and credit card issuers, this is an important arena to keep an eye on. As regulations change over time (including recent laws that have made it harder for individuals to declare bankruptcy), the fortunes of some major businesses, along with those of their customers, will also change.

Learn more in our Credit Center, which also features some surprisingly interesting info about the credit card industry. Being smart about credit can potentially save you tens of thousands of dollars. Check out the following articles:

You can also read about all things credit-related on our Consumer Credit / Credit Cards discussion board.

Longtime Fool contributor Selena Maranjian does not own shares of any companies mentioned in this article. JPMorgan Chase is a Motley Fool Income Investor pick. The Fool has a disclosure policy.