I wouldn't know. I barely got into solid food in the 60's. I went through there in the late 80's. I'd think all they had in the 50's was Kentucky fried chicken, drive-in theaters and mom & pop hamburger joints.
I was a big Domilise's (New Orleans) guy, but it has become inconsistent since the owner died. Radosta's in Old Metairie and Parkway in New Orleans are probably my favorite (shrimp) po-boys.