You want to live-it up reading /r/Frugal by the lake while leaving literally tens-of-thousands on the table, fine. Selling yourself short takes zero effort. There's always someone in line to undercut.
But don't kid yourself - your ability to be thrifty isn't a virtue in this context. You steal experiences from yourself, your family, and you jeopardize your health and safety by not demanding appropriate compensation for the value you bring.
I don't know you, but you're probably a great engineer. And if they can pay some guy on the coast a fantastic salary, then they can find a way to pay you the same fantastic salary.