You didn't read the article, did you? Let me know when you do. Until then, I think your use of the word "pompous" is a bad case of projection.
Please use your amply freedom to explain how these stores are different, I seriously doubt you can, but I am anxiously awaiting your attempt.
Simply put, Wal-Mart makes bigger demands on its suppliers that they can't ignore because Wal-Mart is such a substantial segment of the US retail market. It is similar to what Microsoft has been able to get away with because of their dominance of the software market. Monopolies are bad in a capitalist marketplace and near monopolies are often nearly as bad.
Music companies put out special versions of albums with censored lyrics so they can sell them at Wal-Mart. While I personally think this is a good thing (in this case, it gives parents a way to buy sanitized music for their children), can you imagine a K-Mart, Target, or Costco demanding and getting such a concession from the music industry? They didn't and I can't.
I read your article and if your whole argument is based on this biased, semi hatchet job, no wonder you don't truly understand.
BTW, why do you take this article as gospel?