If US or EU inflation hit 2000% there would be global consequences. There is no reserve asset currently large enough to redenominate US denominated assets, aid payments would collapse, and currencies pegged to the dollar would collapse. Betting on BTC for such a world is reasonable, as there would be a reasonable chance your gold reserves would be become inaccessible, seized, or both. However ammunition might be a more effective financial hedge in this situation.
If they're allowed to. Which underscores that the true innovation of Bitcoin is to circumvent rules and regulations.
How are they going to buy groceries with their BTC? Pay rent? Taxes?
Go to the local black market and exchange it for local currency? You can do that just fine with USD, too.
Does doing black-market deals in BTC somehow make you immune to arrest, prosecution, and execution?