Note: Putting this in Web Features even though it encompasses all of the categories.
As a Roblox developer, it is currently impossible to prevent others from using your assets and game content even when you do not make it public.
This item is created by me. It’s not for sale–I have slaved over it for hundreds of hours and have poured my heart and soul into it. I would be crushed, should it be used in someone else’s game without credit. Fortunately, since it is offsale, nobody can possibly take it–
10 seconds. It took me 10 seconds to rip an asset that was offsale.
To remedy this situation, I would suggest that offsale assets become “invisible”–in a simiar fashion to YouTube’s unlisted system, an offsale asset would not appear anywhere to anyone but the creator, unless they had the direct link to it.