As I said earlier, copies were made by hand by people who could make a fortune these days as forgers. Just because a person could faithfully copy an important document doesn’t mean he was good at punctuation too. I believe there were at least thirteen first generation copies made - one for each state - and no one knows how many more were made from those copies. Every one of those required someone with a steady hand and a good sense of what he was doing. I’m sure some of those copiers were better than others and made mistakes. Heck, my supposed photocopy might actually be from one of those copies of copies.
That reminds me of the story about the printer who set July 4, 1776 into history when it was actually supposed to be July 2!
Punctuation conventions change over time, and there are different styles of punctuation that are observed even today. We are in a more "when in doubt, leave it out" mode than in the past. I am wondering if that is why it was taken out of my copy on the wall, because it appears to be something that may have been used in a school, and perhaps they "corrected" the punctuation. Or it may have simply been a mistake, or the printer thought it was a mistake and "fixed" it?