I saw this at the cinema in about January 1984. It was at an early Saturday matinee. There was about a dozen people in the theater. I was with two brothers that I used to hangout with who were zombie fanatics.
My strongest memory is of the scene when the zombies spilled out of the plane and were running and using weapons. We just all looked at each other like wtf. My two friends both hated the film, but I loved it. They were mad because the zombies weren't acting the way that zombies are supposed to act. They also hated the ending. The younger brother actually saw someone that he went to school with in the theater. I remember him saying that they would have something to talk about in school on Monday.
It's strange that the older brother always claimed to hate the film, yet every now and then when he was at my house he would ask to watch my tape of it. I guess it must have grown on him.
It's funny for me to think of how different things were back then. I lived in a fairly small town. There were only three cinemas, with I believe seven screens between them. Yet oddball B-movies like City of the Walking Dead and Pieces could still make their way to town.