I would see no reason for me to get a top of the line 3D printer unless I was working with something other than plastic. I have seen a 3D printer where it uses concrete and created a house. Now that is something that is interesting to me.
There's really not a whole lot of reasons to need a very fancy 3D printer; however, the cheap ones are kind of prone to getting plugged up with material and misaligning (And of course they are expensive to fix). If you are making something with metal to sell as jewelry, and it is going to be small, a good printer would be useful. If you are printing parts for a machine, a good printer would probably also be wise.
A concrete printer sounds pretty cool. It would probably have to be really big though.
Three-dimensional printing allows extremely small and complex structures to be made even in small series. A new method now allows glass to be used for this technique. As a consequence of the properties of glass, such as transparency, thermal stability and resistance to acids, the use of this material in 3D-printing opens up manifold new applications in production and research, such as optics, data transmission, and biotechnology. Ref. Source 4k.