I think yes, an old casino which has been very active here on the forum should have a large number of regular customers. All these older customers will not disappear just because the casino is cutting down on its advertising. The only change I would expect to see is a dropping number of new customers to join the casino. I think when it comes to advertising budgets the casinos can run a case study to see how many new customers they get per week with various advertising channels. In the end it's a cost/benefit analysis to see if it's really worth it. Let's say the casino notices that 80% of their revenues from existing gamblers and most of the new gamblers leave the casino after a few weeks. Then it could much better for the casino to run promotions directly for the older customers. Instead of paying for advertising they could make weekly giveaways for regular customers.