Wal-Mart could undercut sales of major brands

Costco (COST) has a large line of private label products. People who do not want to buy name-brand products and pay the premiums can buy similar products created for Costco and buy them at a substantial discount. The trend is moving to Wal-Mart (WMT) and, because of its size, the move could cost premium product producers a lot of sales.

According toMarketWatch, "Wal-Mart this month reintroduced its Great Value brand, first unveiled in 1993, with expansion into 80 new products, from organic cage-free eggs to thin-crust pizza."