Forget about the blues plaguing most retailers: Business is booming at Dollar General Corp., with first-quarter sales and profits up in the double digits. The Goodlettsville, Tenn.-based company says its first-quarter sales shot up 15.7% to $2.78 billion, and net income soared to $83 million from $5.9 million a year ago. On a same-store basis, sales gained 13.3% for the quarter.

And yes, many of these gains are due to the poor economy, and broke consumers looking to save money wherever they can. But there's also growing evidence that consumers -- especially those in higher income brackets -- like shopping at dollar stores, which tend to be smaller and more manageable than other discounters.

"Customers are responding positively to the changes we are making in our stores as well as to our continued commitment to providing convenience and great value," the company says in its release. "Our loyal customers are shopping with us more often, and we believe that we are also attracting new customers."

Last week, Dollar Tree -- a Chesapeake, Va.-based competitor -- also reported banner results, with its first-quarter sales jumping 14.2% to $1.2 billion, and comparable-store sales climbing 9.2%. "As consumers are searching for ways to balance their budgets in these uncertain times, more of them are turning to Dollar Tree and finding exceptionally high value merchandise and a fun, convenient shopping experience."

Rival Family Dollar is scheduled to report its results later this week.

Dollar stores are increasingly appealing to many types of shoppers. Nielsen reports that high-income shoppers spent 18% more at dollar stores in the second half of 2008 compared to the prior year, and that growth at these stores is outpacing other shopping channels at both and high and low income levels, attracting an estimated 65 million U.S. consumers in 2008.

Still, lower-income shoppers remain the core business, with Nielsen reporting that 45% of dollar-store sales come from households earning $30,000 a year or less, 47% from those earnings between $30,000 and $99,999, with just 9% from households earning $100,000 or more.

The most commonly purchased household items, Nielsen says, are paper goods, detergent, trash bags, and cleaning and laundry supplies, with candy, snacks and cookies the most common edible purchases.

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