Teaching not playful? I really hope you're not in the teaching profession! I would argue that any profession that involves interaction with other human beings (ands that's a lot of them, in our current service/information based economy) has some level of the 'playful' involved.
Perhaps your understanding of play isn't the same as I imagine Pat Kane might be advocating (I've just ordered this book as part of my MA Education studies, so I'm guessing) but I think the real incompatibility of views here is that you seem to accept the Capitalist structure of society as an unchangeable 'reality' - i.e. that the only achievements of value are 'profits' and 'targets'
I agree that to a large extent this *is* the society we live in, and that cannot be ignored, but is that a reason to accept it unquestioningly as we strive to make our way in it?
For me, the *work* of play is in taking the risk to genuinely engage with the humanity of every individual I come into contact with - to see beyond people's professions, economic status, what they might do or demand from me. For many, especially those who have bought into the values of our still largely Capitalist-driven society, this is too great a risk: as the pay-offs cannot always be measured in the ways - i.e. 'power...wealth and status' - you seem to think are the only valuable achievements.