She said "she loves her cats to death", and the reason she's doing this is because she has to many. In speaking to her, she really has no clue. It's 17 degrees here now, and it's been snowing all day. A barn is not going to shelter this cat from the cold weather, it will keep it out of the snow, but there will be no escape from the freezing and cold. And unless someone is diligent about feeding the barn cats, and keep heated water available for them to drink, these cats will have to very quickly learn to fend for them selves.
These cats are used to being in warm weather, this is NOT the time of year to be putting a cat out to the barn, but she says "it won't hurt them, they'll be fine." Cruel!