I did the same thing. Once. I took a 10 cent plastic “Tommy gun” (not full size) from the local Ben Franklin 5&10. After three days I was so ashamed and scared that the police would come for me that I confessed to my mother and begged her to take me back to the store to return it before they could arrest me. It was my one and only venture into crime....
When we still had a k-mart in town, one of my daughters lifted one of the monopoly pieces from a box.
We discovered it in the van going home, and my husband turned around and escorted her back into the k-mart to return the piece to the manager.
I think she was 6 or 7 at the time, too.