Will I be banned by my casino if I place a bet that is higher than the promotion’s permitted bet size?
If the casino investigates your account and believes that the bet in question is enough reasoning to warrant a ban, then you could indeed lose access to your account. However, the possibility of this happening is usually pointed out in the casino’s terms and conditions. If the casino simply says that you will lose your bonus should you wager over the limit, then you are unlikely to be banned.