At least in high population places like much of California, nobody controls distribution and placement to this degree. If you are not happy with Safeway - and there is no reason to be - you can buy some product categories at the other chains, at walmart or Costco, unpackaged at specialized grocery stores, at several kinds of ethnic grocery stores, even at eastern european grocery stores. And that's before getting to online, long distance, grocery delivery which is not even always out of the question on price. ALL of these are functional. We do have a lot of choice currently.
Not when a cartel controls 97% of the market, distribution, placement, and is very keen on maintaining the status quo, as posited by the article.