Uhm, which downtowns? Seattle has a few grocery stores downtown, they even have a target. Downtown Bellevue has a Safeway, QFC, and an H-mart. LA, SF....have thriving downtowns with grocery stores. They aren’t huge, but they aren’t invisible either.

Even red-state St. Louis had a grocery store downtown, though it took a bit to find one near the hotel I was staying at.