Ironically, I see pretty effective tornado effects in movies all the time, using polygons. An audience will happily believe that a tornado is composed of solid pieces of geometry (such as a car, or a cow, or individual roofing tiles) because they've seen it on TV. Tornadoes do not deconstitute matter as far as I'm aware. Thus hierarchical polygon models are ideal for tornadoes.
Also I feel like your example is confused, I'm trying to be polite, but I think you should do some research about what this is before writing a counterpoint like you have. (what you've written isn't really meaningful.)
Let's take an example of a whirl wind in a desert or dusty plain, in a polygon mesh you're not seeing individual sand grains being lifted from the polygon surface then flying around and landing somewhere else forming a pile, as you have suggested. In a voxel simulation you would however see just that.
Now ignoring post production, what you're seeing is a well textured, but (crucially) introduced, particle effect and maybe some surface deformation for the sandy hill that is being destroyed. (This isn't how the effect is done in film by the way.)
Translating (i.e moving) cows and other objects is actually more on par with how voxels work. I.e. moving an object through space and placing it somewhere else. So you were half right in your thinking that way.
To finalise my point, the tornado "mod" example that I cited wasn't me discounting polygons as you've interpreted, it was referencing this video specifically(i.e showing how voxels can trivialise the programming of advanced motion effects): http://www.youtube.com/watch?v=fSEwU5IqZ4A
A simple example of the difference this affords is that large dynamic changes(e.g. a tornado 'mod') are the result of simply moving voxels around and letting the world renderer do it's thing. Where a polygon based system has to computationally alter the various surfaces to represent the changes made, which can be quite a bit more 'work' for programming the various scenarios.