1. This only applies to market orders.
2. Bitfinex is not the only exchange where people can trade BTC or other crypto.
3. How does B acquire BTC for $X at scale?
1. They can see an order match for a limit order and preempt it with a better offer before pushing it through by a micro-fraction of a penny
2. They can run trading bots on all major exchanges to keep USDT pegged —- while not foolproof it will hold in most situations provided there is enough liquidity in their accounts on every exchange.
