The government are right to think that way, it doesn't matter whether the warning is there or not, that one ads can not make any difference unless every ads has to implement the same pattern of giving a strict warning to players about addiction. While this ads you watch had this warning, how about the other many ads that says otherwise? If the government looks into it, they know that there so many other misleading gambling ads which needs to be stopped because it has made people to get ruined by gambling.
This is why if gaining ads can pass some kind of check under a separate agency that will oversee them before they are being posted or presented, that will be really nice, because some gambling sites show warning signs; that's for those that want to pass the positive information, while some are just very convincing, which will mislead those who don't run their own personal research about gambling and can believe whatever they see online.