Funny thing, I actually saw a caboose on a freight train about a year ago on a track in Eastern Ark. So, I asked my logistics guru Brother and he said on occasion that they are used so that sensitive freight that has high probability of theft attempts (Nike Shoes) can be watched 24/7. He was in charge of the ATT distribution center at the launch of the Iphone. They had folks all over trying to steal shipments in route to the DC in Memphis. Even with gps tracking devices embedded, they lost one container full that was jacked in Mississippi at a truck stop, likely the driver was involved and out of the port of Miami before the FBI got there. Cuban Mafia were the likely culprits.