No. Nobody wore flip flops in the 80's. It was a more genteel time where women wore elaborate dresses and men were dashing in full and proper suits hand tailored by the finest craftsmen. Also cars weren't invented yet and people rode on horses and other hooved animals to travel the countryside. So flip-flops would not be acceptable to a 1780's party
In the 70's and 80's flip flops were also called thongs and zoris. They weren't as nice as they are now. Mostly made of cheap rubber-unlike the nicer "Havianas" that we have now! We also wore espadrilles, huarachis. and shoes made by a company named "Candies."
I was in junior high and high school most of the 80's. I remember wearing high top tennis shoes with the laces all loosened up, and a different colored lace in each shoe. "Flip-flops" were called shower shoes. we wore them in the showers to help prevent the spread of athletes foot and warts.