Photo-Illustration by Jesse Lenz

The mix of stuff each store gets is unique, based on historical munching patterns. “You can go to one store and they sell glazed doughnuts all over the place, but go two miles down the road and that town is buying the cruller,” explains Chuck Taylor, manager of Penske’s Northeast carriage contracts.

Wawa stores are like snowflakes; no two are exactly alike—but basically they’re all snow. The Wildwood Wawa has a neon retro- exterior. Princeton’s has a hippie vibe. Inside, the look is standard: bright and clean, with the carnival-colored beverage case in the back, big posters of food where you order, and the eclectic customer mix of cops, punks, geezers, teens and moms. Ed Herr says the diverse clientele is ideal for when Herr’s test-markets new chip flavors: “They might have a Walmart shopper, a supermarket shopper, a drugstore shopper,” he says.

Because the company is private and refuses to franchise—all stores are Wawa-owned—it has expanded at a consistent but sensible pace, avoiding Wall Street’s destructive imperative to grow at an ever-faster rate. The chain added 24 stores in 2010 and plans to open around 20 more this year. If Wawa wanted, it could expand all the way up and down I-95, from New England to Florida, with little competition, says retail analyst Burt Flickinger. (Wawa dropped stores in Connecticut but has announced a plan to open in Florida in late 2012).

Rather than sprawl too much, the company chooses to backfill where it already dominates and keep existing stores productive. Old Wawas don’t get decrepit; they get spruced up or shut down. As former Wawa president and CEO Dick Wood once articulated: “Leave the stars alone; close the dogs; feed the children; and milk the cows.” Even the gritty Wawa at 17th and Arch gets a face-lift this fall, though Wawa has largely forsaken Center City (and North and West Philly).

Still, there’s a transition in progress, and it hasn’t always been smooth. Traditional Wawas were 2,000 to 3,000 square feet; new Wawas with gas pumps, the only kind the company builds now, are between 5,500 and 7,400 square feet, on three acres or more. Half of all Wawas now sell gasoline. Some communities have pushed back and said no to the bigger footprint. In Berwyn, Wawa abandoned plans after being met with local resistance over traffic and development concerns. In Conshohocken, where Wawa considered adding a location, opponents started a hurtful “Stop Wawa” campaign on Facebook. CEO Stoeckel makes no apologies for the company’s growth.

“We compete with everyone,” he says. “McDonald’s is a competitor, Subway. For things like coffee, our competitors are the big national chains—Starbucks. Competition’s good for the consumer.”

It hasn’t been bad for Wawa, either.