Knowing how to work (i.e. be proactive in their survival) allows kids to feel in control of their life. I equate ability to work with cognitive discipline, and note that depression is easy to succumb to when one is too weak for a change of attitude.
I propose such potential sources of work-shyness as: the illusory sense of accomplishment from video games; hedonism as default response to any emotional problem; escape into internet culture does not condition one's mind for what matters for survival in the real world; internet porn; last but not least, parents may not be able to communicate the appropriate wisdom. In short, too many stupefying distractions of the fast food variety, not enough structure.
It is better for kids to learn to discipline themselves as early on as possible, since it is harder to unlearn old habits as they grow older. It could make the difference between an ADHD diagnosis or not :)
Most importantly, work is a source of happiness, too.