~snip~
Mostly if the bugs are in existing accounts only, they won't really be exploited because you'll be suffering for sure. You are right, it is better to report it immediately with the help of the casino and also hope to have rewards on it, but if this is the case, the casino won't be giving any amount to a user unless they are very generous. Mostly those bugs that were exploited are on new accounts or even without it, which is why bug bounty hunters are finding them and seeing if they can get rewards from them, or worse, if they can't get any.
Casinos, like every other big business, are out for their own interests, not yours. Why would they pay someone who just points out their mistakes?
As for these "bug bounty hunters," you're suggesting they're like some kind of heroes, going around saving the day? Please. Most of them are just trying to get a quick buck. They aren't the White Knights you're painting them to be. If a bug can be exploited, you better believe they will do it, especially if there's no reward on the table. Wake up and smell the reality