My bother lives in Massachusetts where horses can be boarded within city limits if you have a shed/barn and people frequently ride them through town. His coworker had a couple of Morgans, including a 20 year old rescue. That horse was super smart. Once or twice a week it would let itself out of its stall, walk a half mile down the street to the small market that had fruit and veggie stands outside, and help itself to a bunch of carrots. It would then go back home and go back it its stall. The only difference was it couldn't get the stall door latched again. People were aware of horses so he wasn't in danger, and he always stopped and checked both ways before crossing at the crosswalk. She noticed that the door wasn't latched but didn't think anything of it since the horse was inside.

After a few weeks of this, she went to the market and the owner asked her to settle her horse's tab in addition to her purchase. She had no idea he was doing this until that point. Somebody recognized the horse as hers so the owner knew who to hit up for the money.