Destroy all Humans has a destructible environment and only when you reload that level does the city ever rebuild, so to speak. A command or whatever can be written into games like GTA where whatever buildings you might have destroyed will rebuild after a certain time or distance away from the area.
I think maybe one of the problems here though would be the extra processing time required to rebuild the destruction.
If it's rebuilt instantly as soon as a timer expires then there's not much CPU power involved--just swap the original building back in place of the destroyed one.
But given the size of the game world in the GTA games, allowing permanent alterations could be very space-prohibitive. It would definitely be cool, though.
