My epiphany came when someone pointed out that everyone knows what an Ewok is yet the term was never used in Jedi.
That really has nothing (little?) to do with it. Lucas has a name for everything in Star Wars (any episode).
Star Wars (I use that name for the original movie, episode IV, becasue that’s what it’s real name is, IMO) was not made to be considered for merchandising. When it became wildly popular they suddenly realized they had to have a toy line (and everything else) and started producing the action figures, vehicles, play sets and what not. Yet every single entity in the cantina (and movie!) had a name going into the movie. Not after the fact for merchandising purposes.
And every single character, no matter how minor, has a name. The characters sitting with Palpatine in his box at the opera/play/music thing/whatever are by no means used for marketing reasons. Yet they have a name (and race, I should point out). A perusal of any official Star Wars site will find you names for characters you probably don’t even remember seeing. As well as names of races, names of mechanical/science features, ships, planets and just about everything with the least bit of significance in the Galaxy of Star Wars.
So I don’t buy that argument that they were made and named solely for marketing. I’m sure it played a part, but as the sole purpose for the existence and plan for the Ewoks, no.