OK, Moodle is a Learning Management System, a learning tool that is applied from Kindergarten, to University. The biggest user Open University of London has about 250,000 Users. Both Universities I have attended in my home town use Moodle. Moodle is available for all public schools in my home state. So it is a useful tool in the education systems of the world.
Moodle is used as a training tool in hospitals, nfp-ngos as well as government departments all over the world. It is used in theatre companies for Role development, Role Analysis, acting support and technical skill support in theatre. Fast Food franchises use Moodle for their staff, not just training, but for news and such as well. Offline Moodles are developed for places where bandwidth is severely limited, or for prisons where they don't want prisoners communicating with the outside world.
Someone will log in and tell us they are using their Moodle to do something that I had never thought Moodle could be used for. So far, there has not been anywhere that Moodle has not fit or played a role in.
If you are thinking of using Moodle for something, then sit down and think about exactly what it is you want to use Moodle for? Moodle is not a content management system, it is not a learning or learner management system, although, some have argued that Moodle can be these as well.
Be definite about what it is that you want to use Moodle for. It might work, but there may be better tools out there that would better meet your actual need.