People didn't collect knives then like now. The local hardware store had a display of Case, or Schrade, or maybe even Camillus, and that was that. People had a knife. That's "A" knife, singular. If something happened to that knife, or it finally was worn down to a skinny steel toothpick, they tossed it in the tool box and bought another one just like it.
Carl's wonderful post made me think about the displays that Camillus used to present in their old catalogues, and the prevailing idea that knife-buying was so much different back then. At that time, a fixed-blade in the profile and handle material of choice was probably as close to "tactical" as you'd get in a typical retail establishment, while a folder was something you bought for work or recreation without any sort of eye towards self-defense. That got me thinking about how the knives are marketed then versus now, and the state of "collecting" over the years.
Knives were, are, and will forever be tools first and foremost. Manufacturers realized this in the 20th century and marketed their products accordingly. You had knives for the hunter, the fisherman, the bushcrafter, the everyday working man... Whatever your cutlery needs, there was a knife. The key word being "needs", right?
In those days, like today, there was still a pretty big variety of knives available. As Carl pointed out, people would generally select the pattern that most closely fit their cutting needs and stick with that throughout. Some retailers didn't want to carry a full line of knives but they would pick out the segments they wanted to cater to, and manufacturers would often facilitate that. Camillus seemed to be one of the foremost in "tabletop marketing":
I think it's important to remember that there's always been knives which might fit into the (overly wide) realm of "tactical", even in the simpler days. Even years after the the war ended, cutlery companies were every bit as mindful of the military applications of their products as they were the sporting, bushcraft, or everyday "light use" aspects.
One of the documents I have found is the 1951 Government & Defense pamphlet in which Camillus shows off its plant and discusses its history. One might have the impression that they spent much more time marketing to the working man and not necessarily the fighting man, but both during and after times of conflict the factories were more than willing to "go tactical", as indicated by this Korean War-era snippet:
Eventually, civilians started to see "mil spec" and even "space age" creep into their personal knife purchases. Who here hasn't handled one of these steel beauties?
Maybe you've enjoyed a juicy steak with one of these slicers:
Another thing to keep in mind is that the hobby we all share wasn't necessary unheard of. Manufacturers and dealers would produce and sell cutlery with an eye to the hobbyist and the novelty aspects that we take for granted these days. When forging and honing steel first encountered the industrial revolution there might not have been much of a market for "collectors", but that changed once people started to see what we all do in our blades. Eventually, the "marketed to hobbyists" segment appeared (and, clearly, took off):
So while traditional cutlery might have been rooted in the hard-working blue collar man's everyday cutting needs, it started expanding and blossoming into the varied and highly specialized industry we see represented today by custom blade makers, "tactical" folders and even artisan-style pocket jewelry many of us love more than we're willing to admit to outsiders.
And let's all just be glad that cutlers didn't get
too involved in the fashion industry...
(Excuse any image quality issues, I had to screencap the catalogue pages and convert to .jpg to post them. Not the most efficient way.
)
Just for those dress up occasions, ya know. 
