Probably some gamblers are thinking the rules of these casinos are just the same so they don't take time reading the ToS before proceeding to gamble. Then if they already face an issue that's the time they will read the rules to know if they violate one of it in connection to their problem.
I guess they don't read ToS or FAQ before they have problems with their accounts like suspension, lock, ban, can not withdraw their money. Like some people store their cryptocurrency on centralized exchanges and consider their accounts are like non custodial wallets and completely safe. They don't follow those exchange blogs, Twitters and don't know about policy changes like new requirement on KYC. At the end, when their account is restricted, they complained.
I think it is very similar with gamblers on gambling sites as most of them don't read ToS and FAQ. I don't too honestly but I will search with some key words to find information, rules about important terms which can affect my account and my money.