another angle to this is, most kids who go off the rails, when asked why, will answer with things like - i was bored, i hate it round here, lifes crap, nothing to do, nowhere to go, etc and also some would say parents never did stuff with us, never took us anywhere, etc
they are bombarded with images of a better life, with how the other half live, other kids going off on holidays, and many of them wont think they should work harder in school to get that stuff, they will just steal it or get frustrated and act up...and still feel hard done by for having a crap childhood
holidays show them new places, new adventures, new people, new cultures, and above all fun- the type that doesn't involves hanging about in parks with their mates, or being stuck in the house with an xbox
many are desperate to get away from schools
i was lucky my parents could afford to take holidays at any time of year, but many couldnt, and had no choice but to go at the cheap time.