I don't know how I feel. Really.
I was browsing through miniatures listings on Etsy, and I found pieces of my work on another person's diorama. Yes. One of my cabinets has been stripped down, and the pieces used for another person to create a witch house.
No, they are not copies. The potion bottles have my design on them, the filling I put on them inside, the mortar and pestle I crafted are there.
I don't mind somebody using my cabinets to fit the design of their dollhouse. That's why I don't glue the objects down, so they can be arranged to fit the taste of the new owner, to match and mix with other objects or to display in another room.
What I don't know how to take is somebody taking my work, reusing it in another display and saying to the world: "Hey look. I made this".