Grocery stores operate in many different styles ranging from rural family-owned operations, such as IGAs, to boutique chains, such as Whole Foods Market and Trader Joe's, to larger supermarket chain stores. In some places, food cooperatives, or "co-op" markets, owned by their own shoppers, have been popular. However, there has recently been a trend towards larger stores serving larger geographic areas. Very large "all-in-one" hypermarkets such as Walmart, Target, and Meijer have recently forced consolidation of the grocery businesses in some areas, and the entry of variety stores such as Dollar General into rural areas has undercut many traditional grocery stores. The global buying power of such very efficient companies has put an increased financial burden on traditional local grocery stores as well as the national supermarket chains, and many have been caught up in the retail apocalypse of the 2010s.