I think there is one more positive effect of alcohol: creating trust between the drinkers.
Alcohol is like a mild truth serum; it makes it more difficult to create complicated lies, and more likely to tell the truth regardless of the consequences; plus it gives social permission to others to ask awkward questions.
If you come from a drinking culture, then people who refuse to drink with you are obviously the people who want to keep secrets from you, so it makes sense to treat it as a red flag.
Ads follow the logic of spamming. If you send million e-mails and only one person responds, it still may be profitable. Therefore, “my probability of responding to an ad is like one in a million” can be system working as designed.
Even if you 100% only buy things you really need, there is probably more than one supplier, so the function of the ad is to make you buy from this specific supplier, as opposed to their competitors. The fact that you respond to such ad (as opposed to closing the tab, forgetting completely about the ad, and trying to find the solution for your needs from the first principles) is what incentivizes the suppliers to engage in the zero-sum game of spending on ads. Ultimately, the cost of the ads is a part of the total cost of the product. Again, system working as designed.
Sometimes you may be forced by others to follow the ads. For example, imagine that an ad creates common knowledge that “owning X is high-status”. Even if you are 100% resistant to the message, as long as you environment buys it, i.e. everyone around you buys X, and they treat anyone without X as low-status, you maybe be forced to buy X anyway even if you consider the ads laughable (or you have to suffer the consequences of being treated as low-status).
Ads may have greater impact on you when you buy gifts for others. You are less sure about their utility function than you are about yours, so it is easier to nudge you.