I think that most people don't realize the importance of the towboats in the United States. (I'm sure that a few of you do.)
There is a massive amount of items transported on the eastern rivers, with a lot of it going outside of the United States. These huge tows being pushed by towboats are the cheapest way of transporting these type of goods. Much cheaper than trucks trains etc. I don't know what the percentage of the goods transported by towboats and barges are, but it has to be a lot.
So the design of the tow boats have to take into a lot of requirements, depth of the rivers, size/capacity of the locks, wind and weather, navigation hazards, loading and unloading piers, refueling, etc.
Towboats can be found almost anywhere in the United states. In this area of Florida, Tampa is the largest seaport. Tow boats here don't usually have multiple barges, I have seen them used to move fuel barges to the cruise ships. Smaller towboats are usually used for moving construction barges, mostly for bridge building and repair.
This trickles down to the smallest sizes, many about the size equivalent to the rc model Springer tugs. They are often moved about on trailers towed by semis. One that I modeled (see link below) after actually traveled by truck less than 50 yards from the pond we run our model boats in. It was launched into the larger lake adjacent to the park along with some barges.
Lew
rcflorida.org/lmb/lmbs3/
https://share.google/lMPPFJSpUURlWdl2E