Deposit bonuses and trading rebates seem to be free money, but when converted into actual transaction costs, the conclusion is often the opposite. This article dissects the trading volume requirements and withdrawal restrictions attached to the bonus, the overpayment of spread fees to unlock the bonus, and the side effects of excessive trading incentives due to rebates. It provides a conversion idea of ​​"overpayment cost versus promotional value" and reminds novices to treat promotions as additional information rather than the core reason for choosing a platform.