Hermit Crab Housing Star Polyps?

[Dabn AD]

Hello, something funny happen tonight, a reef hermit crab took over my star polyp colony. I never knew it was growing over a shell, but my hermit did haha. His old shell replace my coral and he took off cleaning with a colony behind him. Has this happen to anyone else? I'll try and get pictures but wont he kill my coral by moving and scraping it around everywhere? Its kinda cool but I dont want the dead coral to start messing with my water quality. What do you guys think?