This may not matter in this discussion but if you look at pg 36 in Masayuki Amano's "Live Jewels" General Survey of Fancy Carp
"Further, during the Meiji era (1874-1875, A.D.) superb carp belonging to the "Sarasa", "Asagi (light yellow), and "Ki-utsuri" (yellow-tinted) were brought into exsistence, some of which were so high-priced as fifty yen at the money value in those days. Seeing that carp breeding bordered on speculation, the Prefecture authorities considered it proper to put a temporary stop to the industry. These mountain villages, however, had no other noticeable means of livelihood and pastime, and so the ban was lifted before long."
While he doesn't mention clubs it is clear that koi keeping was a pastime for them which means it was a hobby back then as well. The fact that some of them went for higher prices then others clearly shows some sort of judging was used to classify them as being worth more then others.