Some people have better impulse control than others; it's not the state's job to regulate the impulses of their populaces, or regulate systems that know how to manipulate them.Out of genuine curiosity, do you feel the same about state intervention in other situations, away from gaming, that involve a more knowledgeable or deliberate party taking advantage of a less knowledgeable or deliberate one?
For example, what about full-on gambling where the potential exists to win big but players will probably lose, and having already lost, aggressive tactics are then used to get them to try again? Does it matter whether the person gambling understands the situation they are being steered into?
Is it OK for bars or clubs to offer a happy hour early in the evening to get patrons going, then turn up the heat and make it hard to find water so those patrons keep ordering more drinks and getting more and more drunk throughout the evening?
What about phishing attacks? If someone is ignorant of the possibilities for impersonating e-mail from someone else they know, should we turn a blind eye to those who would send such e-mails to trick someone who thinks they're helping a friend in need into parting with their money?
What about confidence tricksters who do similar things on the doorstep of old people who may not be familiar with what sort of credentials a genuine representative of their water or electricity supplier would carry today?
Or payday loan companies, who will offer what looks like a lifeline to those who have fallen on hard times, yet charge astronomical rates of interest that can rapidly lead into a vicious and sometimes devastating cycle of debt and despair?
How about law firms in jurisdictions where everyone normally pays their own legal costs after a court case, who send threatening letters alleging infringements of copyright and offer to settle for just less than it's likely to cost to go to court to challenge the allegations?
What about outright grooming of children or other vulnerable people for the purposes of sexual exploitation?
For these and many other similar reasons, I think it is appropriate for the state to regulate industries where one party may flagrantly take advantage of another. No-one can possibly be an expert on all areas of society, and laws exist to protect us all from those who would otherwise unfairly take advantage of those weaknesses. Of course there are sometimes grey areas, but the principle that governments should never step in to protect the vulnerable from exploitation seems a very bad one to me.
Also, I dispute your characterisation of the entire marketing and advertising industry as if everyone does these things. Of course all ads are hoping to engage someone in the target market and pique their interest, but IMHO that is a far cry from the kind of active and disproportionate exploitation we're talking about with some of these games companies.