This is an overly pessimistic view that ignores the philosophical aspects of economics. E.g. I lived on under $15k per year for a couple of years before I moved into software development, but during that time I still supported a very liberal approach to economics. This is because I hate violence (I can't even bring myself to crush spiders that wander into the house), and view redistributive economics as necessarily violent, as in a roundabout way it's forcing people to give goods/services/tokens of exchange to me that they may not want to give (since they're forced to give it via taxation lest they face imprisonment, I cannot assume it's voluntary). Other people may not care so much about this and take a more utilitarian approach, focusing on maximising some particular metrics (such as GDP or income equality), so they'll reach different conclusions.
Assuming people subscribe solely to the theories (economic or otherwise) that maximise the financial benefit to them is ironically a rather economics-style view of the world, and I'm fortunate enough to say that most of the people I'm close to don't fit this characterisation.
In terms of actual data, there's a correlation, but it's far from being the strongest factor: http://www.theatlantic.com/business/archive/2012/11/does-you...