I think you're reading way too deeply into it. By "eliminating want" Picard means that humans no longer always want more and more and more at the cost of their own financial security or at the cost of other's financial security.
So... why not just say that instead of stating that eliminating "want" in it's most absolute form? Picard seems to have little to no interest in telling this guy that anything he wants he could probably get without the use of money or lawyers. But no, he just tells them that possessions are a thing of the past and he needs to grow up.