I guess there could be some sense in this. In 1798 the government decided to raise taxes on windows and doors that were considered popular with the rich. So immediately people began walling up their windows in order to avoid paying taxes on them.There are still remains of this around the city. In one of these pictures, they are removing the cinder blocks as the building is renovated (since the tax has long since been removed).
Some trivia about the old buildings in Paris: A law passed in 1962 requires the cleaning (ravalement) of all building facades every 11 years. This law transformed the appearance of Paris from black and gray structures to a city of light and keeps it that way.
