Not all food that gets cooked on a pizza needs a fridge. But either way you’re skipping the point. it’s literally leftovers combined, with or without a fridge. Probably even more so without a fridge if food goes bad faster.
The point is it’s a peasant food made of literally anything because scarcity.
So in all fairness to to the benefit it provides there should be no rule that there has to be a pineapple or not.