There's a difference in price (arbitrage) which allows one to take advantage of through near instant banking (and automated via API -> then they sell USDT to via x P2P transaction into THB and scoop back into USDC and then make money on the spread process mentioned above.
I know people making 10's of millions doing this.
The other method is capital control violations.
X with Fiat goes to X with p2p account x then swaps Fiat to Y who has USDT and wants p2p to their account via Binance.com (etc).
X looses a % (normally around 2.5%) which is less than 7% via the traditional method (lawyer).