To make it a bit provocative: suppose, hypothetically, I'm a competitor of an ecommerce site selling many of the same products. On my product pages, instead of using my own photographs, I simply inline link to the photographs used in (and presumably owned by) my competitor's site. Can they legally prevent me from doing this? I'm not stealing their images, not copying them: simply providing the web address where they're stored so a browser (or app) can access and display them.
Of course, business wise, the competitor can (periodically) update their systems such that the addresses I use display nonsensical photos and have their own website use the updated addresses and show valid images, but this question is just about the legal side of it.