It's like a $5 meal kit for a "BBQ meat feast" that has the recipe, spices, but doesn't include the meat. So once you've visited the specialist butcher and spent a lot more money, now you have the $5 feast.
I'm not sure how expensive it was in the '70s but it is very expensive now. American production is supposed to be scaling up, but only to about 1.5 kg a year.