For me, and because there will never be another episode of Columbo produced, I enjoy delving down into the minutiae. Though I've seen all the episodes many times, I am always on the look out for "just one more thing" that I might not have noticed before, or which might be a fun and unresolved thing about which we can still speculate. It helps keep the series alive a bit, and though I would enjoy it even without those little extras, finding them is delightful. :)

Not only can the name "Frank" be clearly seen, the other interesting thing is that the badge on the ID card says "Sergeant" when the metal badge says "Lieutenant" and the badge number on the id says "235" where the metal badge says "416." If I could post screen caps here, I would do so.