There's so much bad history about gambling, and because many were very religious back then, that's why there are not so many advertisements.

But today? I see billboards of gambling ads, and most of them are regulated by the government. Maybe not in your country, but it is with us. Then, there's social media. I believe the marketing attack in today's era is not on the billboards anymore, it's social media where most people spend their time, and they can easily gamble by just pressing the link or installing the application.

They actually don't need those physical ads anymore. All they need is a good commercial or a popular artist to use in their ads. Make it look more appealing and reputable at the same time.