Most likely the businesses which take crypto-currency keep the coins/tokens in hope they will appreciate in value.
If holding stable coins (USDT,USDC…) they may stake them to get some interest.
Probably it is rare choice to go back to fiat. If too many businesses try to do this they will break the 1:1 peg of the stable coins.
There are around $100 bil. in fiat currency collected from people entering the crypto market.
The crypto market cap. of 2+ trillion in stable coin dollars will be competing to get a slice of the $100 bil. in fiat/paper currency.
