The fact that common ones were listed in general audience documents like day planners and dictionaries should tell you it was important. You can even see commonplace examples pop up in old novels and even movies from time to time — if you don’t know, they can sound like weird slang, which of course is what they are.

Also pretty general purpose: sure, I imagine some companies had special codes, but as they would sell these books at stationary stores they were the kind of thing you’d need to go buy if you list yours or left it at home, say as a traveling salesman. After all, reducing “six units of model “luxury natural” need replenishment” to “AVOCADO SIX REPLENTISH STOP” saves you 5/8ths of an expensive charge probably coming out of your commission.

A hundred years ago a stamp cost a penny, a newspaper or cigar five cents and a five word telegram could cost a dollar (with Western Union that included physical delivery to an address, though you had to tip the boy).