All franchises exist to make money but not all franchises exist to sell merchandise of every kind.
The Alien franchise for example is mostly just a film-medium Franchise with the money coming almost exclusively from the movies. There are some merchandise but it doesn't jump the shark.
Star Wars on the other hand has themed eyeglasses, pyjamas, cereal, toys, bed-spreads, alarm clocks, fans, candy, wallpaper, razors, lamps. Ect...
Almost anything you can put the characters or logo on and sell to people has been made. Lucasfilm essentially created blockbuster merchandising but since Disney bought them it's gone even further, I can't walk down the high-street without seeing some innocuous thing with Star Wars slapped on it in store windows
Makes me sick of seeing them. Too much of a good thing and all that
