You're generalising.  Bitcoin's primary use case will be different depending on any given user's personal preferences.  Within the community we have hodlers, speculators, cypherpunks, idealists, philosophers and more.  Some people will even fit into more than one category.  You use it the way you want, I'll use it how I want, someone else may use it in yet another way.  As such, the primary use case is arguably freedom, because no one is in a position to stop anyone else utilising it in the manner they choose.