I completely agree with everything you wrote. I grew up in a rural community, too. I see how DINKs overspend on things they "need" all the time.
However, something you're missing is the safety premium. Often it's not possible to live modestly in a safe, clean neighborhood with good schools within a reasonable commute distance of work (especially if both spouses work).
The long-term answer might include more telecommuting so people can live in Appalachia and still be productive, but that requires a big cultural shift and doesn't help all jobs and careers.