It's a common approach now to always check the site's reputation before depositing some money. We don't need to spend a long time to do that. If lazy to do that, these users might end up in a scam site where nowadays, even scam sites do have a good site interface and layouts that can lure some visitors to try their site.
Referring to the bet limits you said, you know it's not easy to deal with. Experience is the reason why there are gamblers that are end up responsible.
If you will a limit then you lose, there's an eagerness to continue and break that limit. Responsibe gambling is required there.
I don't think it's a common approach at all, a lot of people would still jump into a casino without even thinking twice if the casino offers them a good bonus and casinos know this, that's why they hire the best marketing experts, and teams that can promote their platforms in the best way possible and create bonuses and promotions that will bring in a lot of users and because every gambler will need to complete a certain wagering requirement, they barely manage to win anything.
So, even if a platform has evil intentions and they are not planning to pay anyone even if it manages to win something, it also uses promotions and bonuses to lure in more gamblers because it knows that apart from reputation and trust, it's the bonuses that can bring people in to gamble with them.