Ok, let's get this straight. Free market capitalism is based on greed. That's the engine that makes it work. The entire basis of capitalism is that everyone acts in his or her own self-interest, to try to get as much as he or she possibly can. That fact is what's supposed to keep the players in check.
Don't get me wrong. Free market capitalism has many failings. The most obvious is the tendency of wealth to concentrate more and more into fewer and fewer hands over time. Another is that naivete and lack of education allow some people to be victimized by others. A third is that people often forsake their long-term interests for short-term gratification. ("I want to drive now. Who cares if the environment is a few degrees warmer in a hundred years?") Also, there's the unspoken collusion that allows, for example, oil companies to jack up prices together, ensuring higher profits for all.
But greed is not a failing of capitalism. It is the basis of it.
So for John McCain or Sarah Palin to say they're against greed is just to say they're against capitalism.