Sam Bankman-Fried, the disgraced founder of crypto exchange FTX and trading firm Alameda Research, has quickly adapted to the economic realities of prison life at New York's Metropolitan Detention Center, utilizing fish to pay for a haircut, the Wall Street Journal reported, citing people familiar with the matter.

Learning from inmates, including a former Honduran president and a Mexico top cop, the former Jane Street trader finds himself a long way from the $30 million Bahamas penthouse crypto-billionaire lifestyle, swapping trading in high-value digital assets to become a mackerel trader — the go-to currency in federal prisons since a ban on cigarettes in 2004.

The trend of using food items like mackerel, known colloquially as “macks” among inmates, as currency in prisons highlights a …