Because at least he's honest:
Hardest to accept, though, is the moral premise implied throughout the [papal] encyclical [Laudato Si]: that the only legitimate human relationships are based on compassion, harmony and love, and that arrangements based on self-interest and competition are inherently destructive.
The pope has a section on work in the encyclical. The section’s heroes are St. Francis of Assisi and monks — emblems of selfless love who seek to return, the pope says, to a state of “original innocence.”
He is relentlessly negative, on the other hand, when describing institutions in which people compete for political power or economic gain. At one point he links self-interest with violence. He comes out against technological advances that will improve productivity by replacing human work. He specifically condemns market-based mechanisms to solve environmental problems, even though these cap-and-trade programs are up and running in places like California.
Moral realists, including Catholic ones, should be able to worship and emulate a God of perfect love and still appreciate systems, like democracy and capitalism, that harness self-interest. But Francis doesn’t seem to have practical strategies for a fallen world. He neglects the obvious truth that the qualities that do harm can often, when carefully directed, do enormous good. Within marriage, lust can lead to childbearing. Within a regulated market, greed can lead to entrepreneurship and economic innovation. Within a constitution, the desire for fame can lead to political greatness.
You would never know from the encyclical that we are living through the greatest reduction in poverty in human history. A raw and rugged capitalism in Asia has led, ironically, to a great expansion of the middle class and great gains in human dignity.
Who needs God when you have the market, and human ingenuity? And besides, is not the market a great green god, put here to save as many of us as it can? And the ones who can't be saved?
Well, the market is cruel; but it is just. The perfect god for a fallen world.