For the younger worker, it’s smart marketing. “Say, are you sick of staying on a treadmill, watching your dream of owning a home in a decent neighborhood slip away? Effectively losing money every year as the real estate market skyrockets out of sight, unwilling to bet on the “greater fool” dynamic of overheated markets to be house-poor for the majority of your adult life? That place/State where you’re working hates you, and they show it by making everything worthwhile too expensive and too time-consuming.
But we in Michigan love you and will care for you and we prove it in the most American way possible by giving you $15K upfront. In some of our towns, that’s almost a down payment on a house, a nice house in a safe neighborhood that would cost twice/three times/four times/...as compared to that overhyped overpriced tech slum you’re “living” in now. In a market much less likely to collapse than where you’re struggling to get a down payment.
And with people who are friendly and think you and your income are really quite amazing and will bend over backwards to help you out. They will be genuinely happy to have you as a new resident of your new town. Won’t that feel wonderful, as you settle into that town that fits you like a warm glove on a cold winter night.”
And there are many towns like that in every State of the Union. But Michigan offers $15K in good faith to get you started. Michigan wants you. You are special to Michigan. That’s a powerful message...
And the older worker will have much of their retirement funds spent wherever they choose to retire to. Why not spend them in a place that expresses its appreciation upfront in the form of a love letter written in gold?
I know of at least a few places that do/did sort of a globally averaged salary - their rates aren’t adjusted for location, but if you’re in a major North American city you might be disappointed. If you’re rural, or in less expensive parts of the world, their salaries were well above market.
Tax domicile is a real concern. The BigTech firms are smart enough to know and care where your actual legal residence is, and presumably they’re not going to let you pretend to be in SF to collect SF-adjusted wages while actually living in Michigan and collecting their legal benefits.
You're not worth more if you live in a different city.
The seller has to agree on the price. You're hearing lots of unhappy sellers.