That's where you went wrong - movement parts as you suggest are replaced if they are worn out, but that's not the primary concern here obviously.
I return movement parts because they are not my parts, but the watch owner's parts. If they want to throw them out or keep them, that's their business. Years ago I used to toss all the old mainsprings in the garbage, but had one collector ask me to make sure to send the old mainspring back, so I had to dig that one out of the garbage. Why does someone want an old greasy mainspring? I have no idea, but I now send it all back and let the customer decide. Well I send back everything I can - when I have to scrape out the case back gasket because it's turned to black goop, it's difficult to send back:
I'm just waiting for someone to ask me to filter the dirt out of my ultrasonic tank from cleaning the case and bracelet, so they can have the original dirt back that was on the watch. Hasn't happened...yet...
😉
Anything cosmetic can have value, so old crowns, pushers, dials, hands, bezels, etc. Rolex does not give you these back, but Omega does. It would be better if they didn't remove them in the first place, but at least you have the opportunity to put the watch back to it's previous cosmetic condition when they give you those back. Rolex can potentially devalue your watch by 10's of thousands, make you pay for the privilege as you have to buy new parts, and then steal your property in the process.
Cheers, Al