After a night out on “the Strip,” folks would stop by Foo Foo’s Steak House to pick up a Mammer Jammer sandwich to eat on the way home.
In his autobiography, You Only Rock Once, Jerry Blavat, “the Geator with the Heator,” shared memories of Sammy Davis Jr.:
I remembered how he would call me every time he appeared at the Latin [Casino] and ask if I would go to Foo-Foo’s in West Philadelphia and get his “mammajamma” sandwiches.
James “Foo Foo” Ragan, a numbers banker (illegal street lottery) and nightlife king, opened his eponymous restaurant in 1963. Foo Foo was featured on Gilbey’s Gin billboards in Philadelphia.
From Black Brothers Inc.: The Violent Rise and Fall of Philadelphia’s Black Mafia:
Notwithstanding Ragan’s criminal history, he soon found himself as an extension of the Black Mafia’s racket. “The older heads like [Gus] Lacy and Ragan were given a choice: come in out of the rain or stay out there in the cold,” said one informer. “They hadn’t salted any money away and they were too old to take on the opposition, so they fell into line. The old saying used to be, “You can’t fight City Hall.” Now the saying is, “You can’t buck the system, and this is the system.”
This page from the “Black Mafia notebook” confiscated by the Philadelphia Police Department Organized Crime Unit shows Foo Foo was being shaken down for a weekly “street tax.”
All That Philly Jazz 
Foo Foos was not on the corner of 52d and Locust. It was on the south side of Locust Street several buildings down west of 52d Street. When Foo Foos was in business, the Locust Theater was on the northwest corner of 52d and Locust, as depicted in the picture shown here.