Ok, and then there are people like one of my closest friends who do need two incomes to just make it. She's in IT, works 60-80 hours a week and on call 24 hours a day, he is a medical Dr., together they make just over 200k a year. However, they have 3 kids, a toddler and surprise twins who are 1 (they aren't having anymore). They bought a house about 6 years ago, before prices were crazy, but it still isn't cheap as they live in California. The husband has several hundred thousand in student loans, and she has about 25k from undergrad and grad, both have to be repaid. And then there's saving for retirement, his insurance, child care costs, putting money away for the kids education, gas prices, utility costs, basic food costs, etc.
Yes, there is an issue with consumer society. But, for many one income will not do for a whole family and splurging on non-necessities, "I'll just put it on a credit card" behavior has nothing to do with it.