The more people who become addicted, the greater the profits are earned by the company. We have seen many kinds of promotions carried out, even to the point where people within the company offer everyone to use their site. Instead of promising a bigger winning percentage for new users, this certainly invites people to get addicted and makes its users addicted to continue gambling. They will not care if their users become very addicted; the most important thing is that the company earns huge profits from the many people who are addicted to continue playing in it.
I don't think casinos force people to gamble at their casinos. Their advertising is a natural part of any company, and they do it to profit from the large number of players. However, I don't think they have any intention of making players addicted to gambling. Those who become addicted to gambling are their own choices, and therefore, they bear the risk themselves.
I believe the casinos already profit from the sheer number of players, and the addiction to gambling is likely a bonus for them, as it offers a potential long-term benefit.