He would not be the first nor the last man focused on power who had a taste for austerity. The luxuries and pleasures they crave are more abstract. However, as another poster said, this is probably a location to which he has access, rather than his domicile.
Putin lives austerely, eats sparingly, keeps himself in shape. Historically, that’s a key to survival in power in Russia. Peter the Great, anyone? This is no show, IMO.
The vanished Imperial aristocracy observed no such rules, and they died for it by the tens of thousands if they weren’t lucky enough to be able to flee from the murdering Bolsheviks.
Putin's been good for Russia - maybe that's what matters to him...