my understanding is that those are what holds the pricing data, as there is a limit to how much each addon can store, so it basically uses these "data" addons that are listed to store the data
so if you delete those im not sure the addon would even function, not to mention probably lose all your sales data lol
i have my main house (grand topal hideaway) listed in the housing tours, it has multiple target dummies, scribing altar, and grandmaster stations (in progress being filled out), as well as almost every antiquity furnishing on display to preview them
www.esoui.com -> addon search -> master merchant -> description and comments 1st sticky post hold FAQ links where all that is described in detail afaik