So if you decide to flee the country, five pounds of gold is $150K and can easily be carried in a small backpack. Let's say you keep it in 1 troy oz pieces, so you have 80 of them worth about $1800 each. You can go to any nation on earth, and whatever currency they have, they will be happy to sell it to you for gold. Yes, only in $1800 pieces. That's fine, you can exchange it for whatever local currency is being used as you need it.
You can do this anonymously and privately. You don't need to worry about whether the US dollar has collapsed. Gold does go up and down, but it never goes to zero, and tends to do well in crisis situations and maintain value over the long term. It is not - or shouldn't be viewed as -- an "investment", it's insurance. It costs money.
Moreover even if you do not flee the country, having assets that you possess - true bearer assets -- is superior than assets others hold for you in a custodial account. How secure is your 401K? Secure until congress passes a law to take some of it. How secure is your bank account? It is as secure as someone who can convince the bank to freeze your account or close your account. So having a bit of gold or cash as a type of hedge for unlikely events makes sense to a lot of people.
You have to keep in mind that for a household living in Silesia, between 1880 and 2000, they would have lived through one hyperinflation, two world wars, two revolutions and three uprisings, and four foreign invasions. They would have been ruled by Prussia, Poland, Nazi Germany, Soviet-controlled Poland, finally free Poland. Each of these had their own currency regimes and currency reforms. That household would have been well off having a bit of gold tucked away. They would have been able to trade some of it for food during the Weimar collapse, and to transport some wealth through the dark days of communism -- maybe even bribing someone to let them escape the country with something more useful that worthless zlotys in whichever nation they landed.