If teenagers wanted to be like adults they wouldn't be shoplifting nailpolish from drugstores or hanging off overpasses to spray I LOVE YOU LISA on the arch. If they really aspired to "mature status" they would be doing boring adult things like sorting the laundry and figuring out their income taxes. Teenagers aren't tring to be like adults: they are trying to distinguish themselves from adults.But I don't think that critique makes much sense. Harris would probably agree that some people would like to be like Hollywood stars, but that doesn't mean they dream of learning lines from screenplays by heart. They want to drive big cars and wear expensive dresses. They only want the fun parts. Likewise, teenagers want the nice parts of adulthood (like money and booze), but not the others (laundry, tax forms).
But that doesn't distinguish teenagers from others: who doesn't want nice things? The core idea of Moffitt's theory is that teenagers are adults biologically, but children socially ("maturity gap"). And it is not other teenagers or children who treat teenagers like children, it is the adults. To use Harris's own, somewhat exaggerated, metaphor, adults are to teenagers as prison wardens are to prisoners. And I think it's fair to say that prisoners want to be like prison wards in terms of holding the power, but that doesn't mean they're going to go and imitate everything the prison wardens do.
On the contrary: that would be brown-nosing. Instead, what you want to do as a prisoner to signal your power is defy the wardens as often as you can. Likewise, if a teenager wants to signal to his peers that he has power, he ought to do lots of things that adults don't want him to do. That's why it makes sense to steal even stuff you don't want, as is common among delinquents. Much human behaviour that otherwise doesn't seem to make a lot of sense, I submit, can be understood as signaling power, the ability to have one's way even in the face of opposition**.
Andy McKenzie has submitted the view that those behaviours are seen as cool that "emphasize short run outcomes over long term outcomes". I think that's true, but it's only a special case of a broader theory. These behaviours, I think, are seen as cool because they signal that you're not intimidated by the negative consequences of your behaviour, such as ruining your teeth when you use them to open a bottle. (The authority you're defying in this case is nature.) For teens, there's an additional payoff: adults want them to behave in a far-sighted manner. This explains why both adults and teens enjoy not thinking about long-term consequences, but teens more so. It also suggests teens shouldn't do the laundry even if they enjoy it: adults certainly wouldn't mind.
The view of teenage cool as emphasizing short-run outcomes vs. being disapproved by adults are not that easy to test against each other because the two typically go together. But I predict that at given levels of shortsightedness, things will be seen as more cool the more adults disapprove of them. Or perhaps it's adult disapproval of behaviour by teens divided by adult disapproval of same behaviour by adults. I'm not sure which.
*The Nurture Assumption, p. 264
**My loose translation of Max Weber's famous definition