This really shouldn't be a suprise, but the "market forces" solution would involve charging for street parking. That works perfectly fine.
> The reason you don't have a corner store is your neighbors don't want it.
You're sort-of right, but the reality is that walkable & dense mixed use neighborhoods are in high demand in North America, that's why they're so filthy expensive. Ultimately, this needs to get handled by local politics. People need to be able to talk about what they want their spaces to look like and go out and vote.
Street parking isn't governed by market forces. At least how most people use them. I've rarely heard "market forces" used to refer to monopolies or government services that can operate with a subsidy.
I somebody who paid for his house, pays his taxes, and votes, just like everybody else. I'm well within my rights to advocate for urban planning that meets my needs and desires.
Neighborhoods aren't static and there's ample evidence that current planning models are broken.
As for parking, consumers of the parking should be paying for it directly. "Free" street parking is not free and takes up considerable space. Parking minimums for many building types require an excess of parking that leaves vast asphalt pads empty most of the time.
Parking is either on street (and therefore a subsidy to the business) or in parking lots. Either parking minimums or street parking requires vast asphalt pads empty most of the time, because you have to account for peak capacity.
Why is the county requiring more parking than the market value? The developer has no incentive to under-build parking - nobody would rent in the building if there wasn't enough parking available.
Edit - Des Moines has 19.4 parking spaces per household. Seattle has >5 per household. Other stats about parking density in the article...
https://www.fastcompany.com/90202222/heres-how-much-space-u-...
The very existence of slums/slumlords suggests that selling substandard housing to desperate people suggests both that there are people willing to accept substandard housing and that it is profitable. If it can work with rat and mold infestations, etc, it can work with an uncomfortably small amount of parking.
I have no idea what the right amount is, but I certainly don't believe your reasoning provides more information.
And it doesn't take mega $$$. If your community wants a corner store you can probably get a variance. The reason people say it takes mega $$$ is because they are asking the zoning commission to do some thing unpopular, and bribes cost money. The reason you don't have a corner store is your neighbors don't want it. And who the hell are you to move in and tell them they're wrong?
There are advantages and disadvantages of being in a residential only area.