I agree with you that many don't see Dropbox as more than a storage facility; but in part, I think that's part of the hook DB has had to get folks to pay attention to them. I do think that they did well in having an API available, but that means nothing to the casual customer unless they are using something more than the norm (I'm not so casual, I use a Nokia N9 and the updated API from DB means that native integration into the file system no longer works for me).
On the other hand, one has to be more of an evangelist as to what DB can do. I use it right now to host my single-page website. Its a simple page, and a hodge-podge of things that I've learned from Winer and others, while also using much code from elsewhere to create what I have there. To that end, I think I'm expressing DB exactly the way they were wanting for many people to use it. To make it one part a destination for a file (as it is for some logo and CV assets for me), but in another part make it a place where you can pull together the web from other areas and create something that's all together similar and different.
That's not a normal way of thinking. And for app devs and evangelists alike, more demonstrations of the possible-impossible needs to happen. Fargo is one of those.