Here is Wikipedia's definition of fine art. It starts out as a simple distinction between aesthetic and utilitarian. But just as in real life, the definition seems to get murkier as it goes deeper into discussion, and where it gets tied up the worse is when it's about which work should be included. Is it traditional art only? Only traditionally recognized mediums?
Artist probably argue over this more than non-artists. It's hard to get recognition in a market geared a certain way, so perhaps artists just want to know where they fit in. I think most of it is elitism though, both in artists and collectors.
Rather than look at a certain style or medium, I like to look at an artist's mindset. First, I do think workmanship has a lot to do with how I think about a piece of art. It doesn't matter if it's a technically difficult realist oil painting or a color splashed abstract, fine delicate sculpt work or rough hewn bold figured clay, there's a difference between what I consider fine art and ordinary art. If you can see shortcuts, i.e.: sloppiness, then it's not 'fine'. If an artist doesn't care enough to take the time to make their work the best it can be, then why should I care about it?
Note that I am not talking about degrees of roughness, that's style, not workmanship.
When looking at mindset then, I can see that the artist cares that their work is to the highest degree possible. That fact alone elevates work into the fine art category for me. There are artists that feel this way, but may not have learned the technique necessary yet, so to me they are budding fine artists...on their way, but not quite there.
And I do not exclude any medium there is that can be used to express an artist's vision, traditional or not. I feel sorry for people that have closed their minds to certain mediums because they're not considered acceptable. I have found fine art not only in traditional guise but more obscure media like digital work, carpentry, food and ice carving and tattooing. There's more, but these come to mind when thinking of artists that are hungry for respect for their work.
There'll always be a fight for recognition of an artist's work one way or another. The point is that getting lost in semantics will get neither the artist or the collector anywhere. To me, plain and simple, fine art is something aesthetic that makes me draw my breath in when I first see it. Sometimes sheer craftsmanship will have that effect, sometimes it's concept or subject matter done a certain way. In the end fine art has that extra piece of heart and soul in it that sets it above the rest.