• by Sarah Mahoney  @mahoney_sarah, August 21, 2008

BJ's Wholesale Club says its net income for the second quarter edged up a bit, to $36.5 million, while sales jumped 17.9% to $2.65 billion. Same-store sales results gained 15.5%, a gain that's impressive even given that 8.1% stems from higher gas prices. The company also bucked a big trend among retailers, and told investors it was raising its earnings guidance for fiscal 2008.

The Natick, Mass.-based BJ's is not the only warehouse club enjoying increased traffic, as shoppers intensify their efforts to get better deals wherever they can. The number of people who shopped at club stores such as Costco, B.J.'s and Sam's Club increased 3.6% from September 2006 to April 2008, according to a new report from Mediamark Research & Intelligence, while the total adult population increased 1.2% in the same time period. And the number of shoppers with a household income of $75,000 has grown 12%. "Upscale consumers have always been a large part of club stores' customer base," the report says. "It's now clear that a greater number of affluent consumers are being careful with their hard-earned dollars during this economic downturn."

Club-store customers are 38% more likely than the average adult to have household incomes of $75,000 or more, 26% more likely to have graduated college, and 32% more likely to hold a job in management, business or finance. They are also 9% more likely to be parents.

Overall, MRI says, 39% of all adult shoppers say they have been inside a club in the last six months.

Still, even these stores are not immune. Several weeks ago, Costco warned investors that next quarterly earnings, scheduled to be announced in October, will be "well below" its former estimates. But even that, the Issaquah, Wash.-based chain says, is linked to inflationary issues, especially energy costs, adding that the outlook for sales is bullish. "Our comparable sales results remain strong relative to other retailers."