The image where a person is walking on a stack of them getting some rope. The image where a person bikes by a tall stack of bikes. For a lot of the properly parked ones, I assume you are right.
Yes, I imagine that may damage some of the bicycles. It's still much cheaper then alternative means of storage. It's just the cost of dealing with industrial quantities of goods - your local big box stores lose or damage some of their merchandise all the time, for similar reasons.