This is the crux of the matter. The market always seeks equilibrium. If there is an income advantage in one location, people will move there, driving up costs in the process, until the point that there is no longer an advantage. Certain cities have held an advantage in earning ability for quite some time and the market is attempting to correct that disparity by increasing costs.
People complain about how expensive these homes are, but in reality they are the cheap ones! The low dollar value homes out in the middle of nowhere are truly the expensive ones. Like you mention, the profitability in a high cost city outpaces the profitability elsewhere, even after you consider that your costs are lower. If the lower paying job, but also the lower expenditures, provided a higher income there would be absolutely no hesitation to take a 'mcjob'.
The question is: At what point does the 'mcjob', where housing is low cost, actually provide – after accounting for costs – a higher income and become the more desirable type of work? That is when housing in the high-priced cities will stabilize, as there is no longer the financial advantage to live there. Until then, expect price to continue upward.