I haven t heard of a guy renting a cow, but I have heard that there is a cow path through buildings in the loop. I did see a show awhile back about this. There are metal doors at 100 W. Monroe that open to a hallway through the building. I have also heard that a cow is walked through this hallway occasionally.
This sounds more like a property easement allowing the man to walk across someone else s property for the purpose of watering his livestock. Laws like this are very real in rural areas. I haven t heard of too many cows wandering in Chicago though. Great story.