Wal-Mart Stores reported Thursday a 2.8 percent rise in quarterly revenues—helped by higher sales at its smaller-format stores and online shoppers. U.S. same-store sales overall were flat but Internet sales signaled a plus.
The company's shares opened slightly lower (click here for the latest quote) after earnings matched second quarter estimates and revenue beat forecasts. The company also lowered full-year guidance.
Chief Executive Doug McMillon blamed intense competition and weak consumer spending for sluggish U.S. same-store sales.
"We're encouraged by the performance of our small-format stores and e-commerce, areas where we're investing significantly this year. But we wanted to see stronger comps overall in Walmart U.S.,'' McMillon said in a statement.
Wal-Mart said its e-commerce business—including store-fulfilled sales—delivered double-digit growth for the second quarter. But the company lowered full-year online sales growth to 25 percent from around 30 percent.
"Generally speaking all the retailers I'm talking to are seeing flat-to-declining store sales and giant increases on the Internet," former Toys R Us Chairman and CEO Gerald Storch told CNBC just after Wal-Mart's earnings release.
"Retailers who have stores are going to have an advantage versus Internet-only retailers," the Storch Advisors CEO said in a "Squawk Box" interview. But that means a duel cost structure, he added. "Retailers are working rapidly to rationalize that model."
Wal-Mart cited increased investment in its online business and higher employee health-care costs as reasons for cutting full-year earnings forecasts from continuing operations to $4.90 to $5.15 per share from $5.10 to $5.45.
Earnings from continuing operations came in at $1.21 a share, on revenue of $120.13 billion. Analysts had expected the company to report $1.21 a share on $119 billion in revenue, according to a consensus estimate from Thomson Reuters.
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Going forward, Wal-Mart has the best chance of beating online sales leader Amazon, said Jan Kniffen, chief executive of retail research and consulting firm J. Rogers Kniffen Worldwide Enterprises.
"We know only about 10 percent of ... [all] sales are coming online," the former department store executive told CNBC on Thursday. "More people buy more online every quarter every year."
Alongside Kniffen on "Squawk Box," ComScore co-founder Gian Fulgoni pointed out that the shift to online shopping is happening at different rates depending on the product category.
"Consumer electronics is probably at the top end with about 30 percent of their sales now done online," but for grocery and consumer packaged products, that percentage is much smaller, around 1.5 percent of sales, Fulgoni said.
Last month, the retailer announced its Walmart U.S. CEO would be leaving the company which has struggled recently to deliver positive comparable sales.
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Since Wal-Mart is the country's biggest retailer, its earnings are watched closely as a gauge of the health of the American consumer.
—By CNBC's Matthew J. Belvedere. Reuters contributed to this report.