Yes it's creepy. But the bottom line is not about google being all-knowing (or not) The bottom line is that adsense is business. Don't start your first business by cheating one of the biggest potential business contacts you will ever have. It's just not wise.
Get the real page with reall traffic first. Then you'll be able to monetize it even without adsense. I would be willing to put ads of my product on any decent site which can give me good and I wouldn't really care the site owner's age, because why?