Mark Wallinger just won the tender to produce the Ebbsfleet Landmark (CGWTF 2016 note: this never got made), which is one of a few high profile public commissions that require the artist to digital visualize their commission. The Fourth Plinth scheme in Trafalgar Square would be another. The weird thing is sometimes they still look like visualisations after installation.
The same problem is illustrated over and over on the website of Claes Oldenburg and Coosje van Bruggen. It shows an impressive catalogue of perfectly rendered public sculptures. Many of these have the qualities of virtual objects - matte or super-shiny, evenly coloured, cartoonified forms which are documented from overhead, apprehended like museum objects on a massive scale.