Um, did some of the commenters really read the article, or any of the linked articles? First, the author mentioned that Walmart is cheap. The produce there is cheap, just like your local Asian market. The kicker is that when you buy cheap imported produce, you're not supported US agriculture. If you are a conscientious consumer, this would be of concern to you.

How hard is it to understand that imported produce means that US produce has to compete against incredibly cheap goods? Because we can't grow produce for those prices, our produce industry suffers. Sure, some mega-farms can compete, but the few family farms that are left can't offer fresh produce for those prices. It's more profitable to grow things like soybeans, corn (used for things other than food now), and wheat - things that are used widely and can be used in junkfood.

It has been shown (go ahead and Google it, since you're so good at Googling) that, calorie for calorie, junk food is cheaper (this has to do with the Farm Bill). And when you are poor, you tend to buy calorie-dense food. It might not be a conscious process, but it does happen. If you have $25 to feed a family, you're probably going to buy packaged stuff with lots of calories, like lunch meats and chips and bread, rather than fresh spinach and carrots.

Anyone who suggests that Whole Foods is a good source for affordable organic veggies needs a good head check.