Transactions can be either off-chain, or on-chain. With former it’s not much different than a database, with latter it’s becomes scammer/terrorist/drug dealer dream.
Also on-chain transfer costs ~$20 in a quiet hour, e.g here is a transfer of ~$250 for a fee of $20: https://etherscan.io/tx/0x7d366b14c99ca6eb457109000f637e59bb...
USDP whitepaper: https://insights.paxos.com/hubfs/USDP-whitepaper.pdf
Contract source: https://github.com/paxosglobal/usdp-contracts
Etherscan: https://etherscan.io/token/0x8e870d67f660d95d5be530380d0ec0b...