There are some things that are merely expensive. But there are also things that are not simply expensive, but which also confer social status and vice versa, which social status makes it obligatory to have. Super exclusive luxury apartments are just such a display of wealth and status for those with the means.
We all know what traditional associations Russian architecture evokes, but are there any modern buildings of which it could be said, hand on heart, that they are clearly and authentically Russian? These days the ultimate compliment for many Russian architects is for somebody to mistake one of their buildings for something somewhere in Western Europe. But not for all of them.