An entire planet that is one big city will never look entirely pristine. There will be older parts of town, run down areas, or areas where the money just isn't being poured into anymore, simply because there are newer, more popular areas. Making the entire planet all look like it was freshly renovated, every building at the same time.....is as unrealistic as all the gamoreans from ROTJ looking identical.

There ARE places that should look spotless.....Padme's apartments, the opera house for example......but we visit enough other parts of the planet....Dexter's diner, the "seedy" club after the speeder chase.......that we should definitely see some variation to the wear and tear.