Krugman speculates that they see this as a morality play wherein the rich are obviously the virtuous heroes (being rich and all) and the plebes are a bunch of lazy, immoral parasites who refuse to carry their weight. I think he's probably right, but I'm going to speculate further that for many of them this is a result of guilt at their own gargantuan selfishness and greed. I can only imagine that it's hard to live with yourself when you're taking more and more of the wealth that humans create while everyone else is falling behind. It must require some psychological jiu-jitsu to look yourself in the mirror and believe that you deserve it.
That's just my personal theory, and the truth is that it's completely uninformed about the psychological make-up of the super-rich. I've met a few and they are the oddest people I've come across in life --- it may be that their psychology is so unique that average people like me simply cannot understand it. (It's also possible that they're just as stupid as everyone else and believe what talking heads on TV tell them about the deficit. Since they aren't affected by the horrors of the larger economy like everyone else is, they just consider them irrelevant.)
Anyway, the key question of why they believe that old people should starve while they hoard every last penny they get their hands on remains obscure. But the fact that they do believe it is indisputable. And as this report from Demos proves, the fact that the political elite of America is in their thrall (as it is in nearly every Western democracy) is also indisputable.
A notable area where the affluent have different priorities is deficit reduction, which wealthier Americans tend to see as more important than other economic priorities, such as job creation. Polls over the past two years have repeatedly found that while many Americans are worried about deficits and the national debt, addressing unemployment and improving the economy has consistently been a bigger priority for the public. For example, a June 2010 NBC News/Wall Street Journal Poll found that 33 percent of Americans named job creation and economic growth as their top priority; 15 percent named “deficit and government spending.” Most polls throughout 2011 and 2012 found that the public remained focused on jobs and the economy over the deficit by two-to-one margins or more.Exit polling on Election Day found that 59 percent of voters rated the economy as the most important issue facing the country, compared to 15 percent who named the deficit.
This is why both parties are obsessed with deficit reduction. They are responding to their patrons and constituents.