All consumer debt is.

This would only work if the "Joneses" are only high consumers sporadically and then pay back the debt. Or they eventually declare bankruptcy. If they are consistently high consumers and they're not declaring bankruptcy they can't just be putting it on credit cards or taking out HELOCs, right?

Seems like there are a few other possible explanations: higher household income than you know, regular infusions of cash from parents, not saving money for retirement, prioritizing spending differently than you do. I'm sure there are other possibilities but in general, debt could only sustain a lifestyle for so long. Eventually that all comes crashing down.