Explanation
This is D&Desque setting with a Modern attitude. Think Flintstones, Dinosaurs, Jetsons...
The mood is meant to be light and amusing.
Unlike other Fantasy Games, DQ(II) is focused on skills instead of classes, but includes Professions instead of being pure skill. Thus, out recent High School Grads can be just starting their professional careers, and still hanging out, griping about Parents not getting it.