Here’s an unsettling look at the Walmart-ification of the U.S., starting in Arkansas in 1962 and ending with total domination more than 3,000 stores across the country. First the chain spreads throughout the state, then the Southeast. Then Walmart crawls north and west, looking for all the world like an invasive species:

If you can believe it, there are even more Walmarts today. That map, by Excel guru Daniel Ferry, only goes through 2006; for a similar map that shows Walmart’s growth through 2010, when it hit 4,393 stores in the U.S., check out Nathan Yau’s version.

The problem is not that Americans are horrible people for buying affordable food. It’s easy to shame Walmart shoppers with thinly veiled classism. It’s harder to propose solutions to fix the food system, eradicate food deserts, protect small businesses, and pay people a living wage so they can afford fresh fare at the farmers market. But that doesn’t mean we shouldn’t try!