But here are a couple of things to consider.
1. If I make more than approx $106k a year, I cap out on paying FICA. 2. As far as I know, everything I buy at places like Amazon costs the same regardless of where I live (with in the US). 3. Many financial incentives are provided as a percentage instead of a raw dollar amount e.g. 401k's are usually matched by percentage, raises are often a percentage increase.
Don't forget that if you earn less money in the same country then you'll pay proportionally less taxes. Made up numbers: CA = 120k gross -> 80k after tax. Another state: 100k gross ->70k after tax; Difference in cost of living: 10k). Now you are breaking even. Of course, totally made up numbers.
And as an extra, for every extra dollar you have in a cheaper state, you can do more with it than in CA.
Sure, I would love to make the same kind of money in the cheapest corner in the world but companies aren't there to make us rich; they are there to have a business! If you want to try to convince company to pay for what you produce instead of paying a fair salary, try contracting instead (and be good at selling yourself)