If you can transfer it to a place where it's acceptable, then it's fine. My 8 year old shiba has a towel and her blanket she's allowed to dig on. I just say the word and she digs away. She started digging on carpet and that was not acceptable, so when I caught her in the act, I put a blanket in front of her and actually encouraged her to dig on the blanket. Now she knows "dig" means that she digs on the blanket and will sometimes pull the blanket into the middle of the living room from the bed room for us to play that game together. At the park I also tell her to "dig" in the sand boxes and she LOVES kicking up the sand there.
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Chelle and the rest of the crew including, but not limited to Kita and Taiko (the shiba inu wrestle maniacs), Adi (reserved and dignified tabby cat), and all 28 reptiles