Yeppers!!Anything I don't want them digging against, I put down bricks, rocks, large branches... anything that's not too easy to budge that I can salvage from the yard. Bedding, dirt, sand, soil, etc all get kicked out of the way too easily.
I keep a stack of pavers and bricks to keep plugging holes.
https://www.backyardchickens.com/threads/excavation-by-birds-a-word-of-warning.1086535/