Our primary use case is having it as our primary sharing and collaboration tool.
Our company is in the entertainment industry. We have lots of different departments like finance, legal, animation, sound, editing — all of that. The actual use case really depends on the department and sometimes the user. For example, I am in our tech department. If I want to share some sort of document with my team, I just put it on OneDrive. Then, if I already shared a folder, I just drop it in that folder and everyone with access to that folder gets access to that file.
That is pretty much how everyone is doing their work and sharing their stuff. They create shared folders and they give permissions to different people as to what they can access and then they put stuff in those folders. That covers our basic use cases.