Thanks to Shawa, who obtained a zoning variance to stay open an hour later in 1997, the spot is usually bustling until 3am.
Referred to by locals as a neighborhood fixture and a home away from home, the restaurant, which opened in 1966, was featured on a 2011 episode of Anthony Bourdain's travel series and has been visited by celebrities like Sean Penn, Nicolas Cage, Dave Chappelle, Keyshia Cole and Draymond Green.
"Many stars, actors, ballplayers loved my father and how he treated them," said Fadi Shawa, who now runs the business with his brothers, Emad and Dani. "No matter who you were, everyone would be treated the same."
When the elder Shawa passed away, chef Tim Luym of Buffalo Theory described him as "the ambassador of Broadway."
Sam's renowned burger isn't fancy, but it's fresh and affordable. Using meat that's freshly ground in-house and sesame-seed buns that are delivered daily, the eatery charges $7.50 for a 1/2 lb. cheeseburger, and $5.50 for a 1/4-pound single.
French fries, fried chicken, shrimp, fish and chips and hot dogs and pizza slices round out the menu; Sam's serves beer, wine and soda, and all purchases are cash-only.
"I can truly tell you my dad poured his soul into each and every last burger," said Shawa, adding that his father's values still inform how he and his brothers run the business.
"'Service with a smile!' And the customer is always right, even when they are drunk and wrong," he added, laughing.
The Shawa brothers are opening three more Sam's locations in the Atlanta area—one outpost is already under construction, and the other two should be open by summer.
They've also recently opened a coffee shop there called Caffeine Atlanta.
As far as the future, Shawa said the restaurant owes its longevity to loyal customers. As a result, no changes are in the works.
"From 'RIP Ed Lee' to Aaron Peskin and his staff to the North Beach Police Department, to the poets and artists that North Beach is known for, the neighborhood will always continue to flourish," said Shawa.
"Not because of Sam's, but because of the special relationship that we have with the community and that the community has with Sam's."
Sam's Pizza and Hamburgers (618 Broadway between Grant and Stockton) is open from 4pm to 3am.
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