[sharker8]

Let me put on my cognitive neuroscience hat. It's because the market for children's books is parents. And parents want a sentimental cognitive effect when reading to their kids (the article mentions 'romanticization' which in cognitive terms is sentimental feelings). I don't know many parents who have sentimental feelings for their upbringings in the suburbs, mainly because by the time they learned what the concept of the 'suburb' is, they were probably entering high school, which is to say, they were entering miniature delayed adulthood, while having to navigate a completely artificial political sphere (high school). That being said I'm sure its a fine story world and captain underpants has certainly done a great job with it.