My FIL's '74 Olds Cutlas S had them. I loved that car and often forget about it. I drove it often and the seats were among the most comfortable I've sat in with the convenience of swiveling toward the door opening to exit the car. There were also many things that I loved about the car.
The ROCKET 350 w/Rochester QUAD, buttery smooth THM tranny and the ride of the car were other things I loved.
My mother's '75 Cutlass coupe. Don't think she or I ever used it as it was one of those solutions for a problem than didn't exist. Quicker to climb in or out with the seat in the normal position.