I don't think casinos with long-standing marketing campaigns can underestimate the results of their strategies. Some have signature campaigns have been running for over five years, along with contest programs and even free bonuses. These brands are the most well-known and their popularity is steadily growing compared to competitors who are still at the beginning of their journey to reach the same level. In a highly competitive market, only the best marketing strategy will determine your position compared to others.
Casinos with long standing campaigns in the forum also create their trust from there. And gamblers use these casinos to play their games more because they have more reliable and trust system. Most of the casinos that comes to the forum want to have traffic to their sites in a short time but it is not possible. Gamblers have to observe your dealings and doings for a long time before many would involve themselves in n the casino activities.
They can't just indulge themselves because you are doing well at the beginning.
Any casino that's known to stay long in this forum is mostly trusted by members here, even though people drop accusations against them, sometimes it's tough to believe, based on how long the casino has stayed in the forum, except the accuser have a strong evidence to back up the claims, even at that their are still people that won’t mind defending such casino depending on how long they've stayed and earned a good reputation.
So I think that marketing their casinos in this forum for a longer period is a good way they can or they'll rather, gain good reputation and trust by members here who could even introduce their friends outside the forum to patronize them, so I believe that many casino should've realised by now that to be relevant here, they need to host campaigns for a longer period.