The President and Vice President are basically on duty all the time. Their house, the plane they use, anytime they travel, they bring their portable office with them. When they leave office, it is normal to have a few classified documents by mistake. And when they are found, they are promptly turned in.

What is different about this case and the Trump case is that both of them appeared to have gathered very highly classified documents, and tried to hide them. The Lt Colonel obviously shouldn't have had any top secret documents at all. Trump lied several times and tried to hide his top secret documents. Even today, there is a report that after the FBI searched his office, classified documents were moved back there in an attempt to hide them.