6 Companies Battling for Americans' Grocery Money (Update1)

BOSTON (TheStreet) -- Consumer-staples retailers are undergoing abrupt changes to their industry. The latest example is the battle over Americans' grocery purchasess being waged by traditional supermarkets, dollar-discount stores, big-box department stores and wholesale clubs.

The fight has grown heated as more retailers of decidedly different stripes are offering refrigerated food products and, in some cases, prepared and fresh foods, which is contributing to a shift in buying habits.

"The latest trend shows consumers making more trips to drug, club and dollar stores, while cutting back on trips to Wal-Mart(WMT) and traditional grocery stores," said Joseph Agnese, an S&P Capital IQ analyst.

And that put a chill into Wal-Mart, the nation's largest grocer. The company said last week it will spend $1 billion this year to cut prices on such goods and is considering allocating another $1 billion to reducing prices next year.