Originally Posted by
lowfareair
But in that case, the person is taking *a completely different item* that the store has and can easily show damages there
With airfares, the "items" are a trip from A to B, or a trip from A to C. If you purchase A to B but actually take more expensive A to C, the difference is the damage.
. . . as they can no longer sell that item.
Irrelevant to legal damages. If you shoplift, the store does not have to prove it would have sold the item you stole to show it had damages.