As if they can produce champagne and other stuff out of nowhere. They may have a nuclear fallout bunker somewhere hidden in a desert but they can only rely on existing food / materials they can accumulate now. Most likely cans of food. Their champagne bottle will run dry unless they’re hiding in a massive Amazon underground warehouse that no one can access it. After all we have seen the riots in Paris, riots in Hongkong, if the law enforcement is not strong enough, people will automatically go riot mode, and if there is really a large conflict, there will be no one protecting the wealthy ones property and everyone is going for themselves