Is there any way to nudge someone in the direction of being less focused on having the nicest toys?

I have a friend who seems absolutely obsessed with talking about his stuff, and what he wants to buy that it gets annoying. Anyhow this pissed off and annoyed several people who interact with him and I on a daily basis.

So they filled all his drawers with newspaper. And then went on to stuff his car full of it. I think it's absolute hilarity. Yet he can't seem to grasp why people would want to do something like that to him.

And yet this same person goes around asking for peoples opinions on which 1700 dollar sound system he should buy. Can he not see how that would annoy people?

If they're jealous that's their problem, but if he's trying on some level to build himself by making them jealous--then he's just being an immature prick and just pretending to be better on account of having nicer stuff..

Sheesh. How do you reform such a character?