Thats because people use the cash in Tether USDT there like their brokerage account: its accumulated from deposit and trading and rarely withdrawn to a bank acc

Thats because people use the cash in Tether USDT there like their brokerage account: its accumulated from deposit and trading and rarely withdrawn to a bank account. For example, if Charles Schwab created Schwab USD upon every fiat deposit, the growth and redemption distribution would be similar to Tether. People that can save and populate an investment account do that more than they ever actually withdraw to cause a redemption.