As I have needed to interact with photographers frequently for various projects at work, and finding myself taking increasing amounts of photos for commercial purposes, I have been doing quite a bit of reading on photography rights and pricing models. While investigating the ASMP (American Society of Media Photographers) site, I found an article on the perils of stock photography. Not only is it an important warning about making sure the photos you are using are unique and not from some overused stockpile, it is quite humorous as well.
Of particular hilarity is An Unsolicited Commercial Love Story. Apparently advertising agencies all around the world use the same stock photography service instead of having pictures taken themselves.
Duplication is a serious problem all over the internet; everything from website designs to body text are blatantly copied with no interesting additional changes or insights on a regular basis on the internet today. Some of it is simply a matter of so many voices having the same ideas that incidental duplication occurs. This is fine and to be expected with billions of people on the internet. Whenever nearly exact duplication occurs on purpose, however, it makes the internet a more boring and noisy place with no benefit.
At the very least we can try to avoid such duplication ourselves, if for no other reason so no one makes web pages making us look as stupid as these advertising "professionals."