The Infamous Third Dimension

 Can a graphic designer be a sculptor?

  This is a bit more of something I'd like to open up to debate rather than a commentary on a particular style. Everybody loves good design and everybody loves good typography but something that I feel is somehow inherently implied with both of these is that there are only two dimensions to them. Typography is almost always done on simply an x and y axis much in the same way a graphic image is. I've seen examples of people like Stefan Sagmeister do astounding things with three dimensional design but other than him I'm afraid I don't have many popular examples. The images I provided are ones I had to go and find but I'm afraid I don't know the artists.
  I suppose what I'd like to know is, at what point is a sculpture a design? At what level does the classical "art" of paintings, statues, and the like become simply design? Does the old Italian argument of "Colorito vs. Designo" come into play? Is Graphic Design exclusively limited to graphics? I'd like to think not and I'd also like to think that they can be concurrent on a great many levels. I'm not the most skilled artist nor the most talented with computers but sculpting and working with a z axis is something I truly love doing. I can't seem to find many places that find that kind of design anything other than experimental though. I would love to be proved wrong on that.
  You could say I have a bit of an old fashioned mind on this subject thinking that sculpture lasts longer than painting but to be honest, they add a sort of flair and intrigue that out cities and citizens need more of. Can a graphic designer work exclusively in 3d and still be called so? Let's start and argument in the comments–all technicalities are considered.