Small stores that stocked specialty items for the local immegrant community and kept the price down (supermarket prices on specialty items are completely unafordable). The successful markets grew and started attracting the more adventurous white folks and other eths, and the markets grew more, still keeping the prices down, and the regular white folks started shopping there.

There's an even bigger multi-ethnic than Sunland Produce out in the far valley but I haven't had a chance to visit it yet.