I think it is enough to attract new gamblers: attractive games & odds to win.
It's somehow depends on players decision if they want to show or not since there are gamblers who love to flex their winnings just to hype up the game they like as well the casino where they played. But to attract new gambler they should conduct more promotions since if they just rely on the winners to post their profits well maybe a short time hype they can accumulate for short time span. But anyways congrats to the winner who win such huge amount of money.