Friday the 13th does not define our society or have a large effect on us, but it is a part of us. It is a quirk and an idea that someone would not be able to laugh about or understand from the outside.
Once again I tried to address what we would lose without cultural superstitions. I still did not have a full understanding so I gave what I could and left it as something the reader could think about, but without directly pointing it out with a question