Every few days I see a new article in my news feed that shows a picture of people wearing the Guy Fawkes masks used by Anonymous. Usually these images are used completely incorrectly.
Anonymous is a group of activists/”hacktivisits” that go after bad behavior on the internet. This group can (essentially) be joined by anyone and generally runs in a highly decentralized manner. There are internal teams that are much more focused. But regardless of this, Anonymous is not simply a group of teenage basement hackers. This is a global group that is focused on a variety of political and social issues and does what they can to bring attention to these issues.
The most common way that their image is misused is in relation to general articles about open source or hacking. Using Anonymous images to cover general internet articles is like using a picture of Occupy Wall Street to talk about a particular stock price going down.
I’ll grant that it makes a little article seem much bigger and sexier but it makes it look like you don’t know what you are talking about.