Because bitcoin is basically a deflationary asset, people in nations with unstable fiat currencies are utilising it more and more as a store of value to guard against hyperinflation and rising prices for basic goods and services. Cryptocurrencies, unlike fiat, can't be as easily manipulated by increased money production and interest rate changes. Most significantly, because there will never be more than 21 million bitcoins created, it is a desirable inflation-resistant store of wealth.