I suspect your time to do 200 fish is not much more than your time to do 20 fish. However, the shipping cost/fish would be drastically different.
There are certainly people in the market to purchase fish that have no clue as to the effort to raise and ship fish. If I was a fish supplier, I might even have a spot on my web page listing the factors you listed above. People are pissed to see a $400 shipping estimate when they get shipping for free on an inanimate item from Amazon. If they see the inputs, then they might better understand the actual associated costs.
I had a guy that lived on an island off of the southern coast of Florida order 2 rainbow trout in August and was very unhappy that I wouldn't ship them....... I sell the trout at around 1# each, I have no idea what it would have cost to ship them.
You are correct on not much more time, BUT if they aren't eyeballs and aholes size wise, I don't think I could ship 200 in one box.....
