Third-party Tools Can Negatively Affect Players Not Using Them

[Absurdity]

"Lots of cosmetic addons are based on cash shop items"

Most cosmetic addon users do not buy cash shop items. Why would they when they can just get a free appearance that "looks way better than anything in game"

Some quick research tells you otherwise.

Mods can't just add new things to the game, they can only visually replace existing ones. Most mod users, as with any other software, have so little knowledge of how this works that they can't choose the item to replace themselves, so if the thing that "looks way better than anything in game" requires them to buy a mogstation outfit they will just do so.