Given a candidate is already in the software industry, the odds of getting a high paying job in the Bay Area are much higher than 0.01%. Top paying companies have the same interview standards everywhere but the number of positions are significantly higher in tech hubs. Not sure why you think your chances are better in the Midwest. Self-defeatist attitude will pull those chances down to zero everywhere though.
There are more jobs paying $300K+ than there are qualified candidates for them otherwise there wouldn't be thousands of job openings for them at any given time.
I rarely see listing that advertise $300k salaries. Where are these thousands of listings? Additionally, many companies leave up listings permanently so they can build up databases of resumes in case they might need you later.
Job's that pay that much don't exist in large quantities period. If you think otherwise, you live in a walled garden.