Disclaimer: I'm no psychologist, but in both my academic and working life I have worked with people like Randy Moss. And I think I know what's going on here.
Randy Moss is ridiculously talented. I don't think people truly appreciate just how good he has been, and how good he continues to be. Despite that, however, he still gets a disproportionate amount of criticism. Giving up. Quitting back at Oakland. Not blocking.
The Oakland thing is interesting. Randy didn't quit on Oakland, Oakland quit on him. Oakland stopped doing everything to win - which is what the NFL is about. Randy isn't like TO, or Ochocinco, he's about playing football, doing his job, and being appreciated for it. Oakland didn't give him that feeling.
Now, the one thing Randy wants is to *be appreciated*. It's that simple. Let me tell you something about money. A lot of people don't want money because they want a Benz, they want the money because that shows them, relatively, how much they are valued. Money, for Moss, is like hugs. It's a symbol that he is wanted, appreciated, and loved. The endorsement contracts he's chasing out of football are the same thing. He wants to be on ads, he wants to be loved, he wants to be mobbed by people. But he's still relatively shy - he's a bit like the amazingly good looking guy who gets frustrated that he doesn't get the chicks but doesn't realize he has to talk to them first!
So, we have a high performer who feels he works his butt off, doesn't get the money he's worth (he feels that if they loved him, they'd pay him early.) He wants the security of a contract now so he feels that they want him around.
Another poor analogy - but if you said to your girlfriend "what are you doing this weekend?" and she said "I don't know, I'll see if I'm free," you'd be hurt too.
ANYWAY. Long story short: pay Randy. Randy will NOT quit. He will NOT get a big head. He just needs to appear on a couple billboards. The Krafts need to pull some favors and get Randy some endorsement dollars, to show that the fans of New England appreciate him. Then sign him for a 2 year extension at 8 million guaranteed a season. It's worth the gamble.
Randy doesn't want money for the same reasons Darelle Revis wants it. He wants to be loved and dollars are the proxy.