If you read what they're advising, it's to use Google image search to locate an instance of the image in use on someone else's (presumably paid use) web site. Short of telling every web site not to use any stock images or to remove Google's image search, I'm not sure what you think anyone can do.
If anyone uses an image without a license - and with so many free images now available, it's not clear why that isn't a better option as it's safe and legal - they're at risk. Established companies are unlikely to put themselves at risk this way, and that's where the bulk of our business comes from