In any case...

In St. Petersburg, at the time the capital and all that, lived an countless number of small officials. They received different ministries and departments inexpensively, practically did not own their own housing, renting apartments and rooms in income houses. However, even in the income house there was a parade staircase and a black staircase. Hence, "go into the parade" and, subsequently, re-think into an independent substantive "parade", applied even to the ignited staircase that goes out for welding.

In Moscow, at the same time, the housing issue was not so acute, the cost of a square meter of land has not yet climbed to such cloudy heights as it is now, and the majority of voters lived in their own houses. Then, as the city grew, instead of building new houses at the hell on the rocks began to adjust to the already existing, but the paths from the street to the house remained, and so that the guest did not accidentally break into the roof, it was necessary to indicate: "House is this, second entrance." Then the streets climbed to the houses, and the word remained.