I'm a great fan of free markets. I am not blind to their flaws, however. They are not magic machines that eliminate cruelty. They take the existing society's morality and amplify the impulses. If you want uplift, capitalism will give it to you efficiently. If you want depravity, capitalism will do the same. If you want theft and violence, well, capitalism will sell you as much of that that the law will allow, even as these two products eat away at the foundations of the capitalist system.
Efficiency, effectiveness, capitalism is fit for purpose as an economy and does very well at that job. Combined with a good moral code and an honest political culture it's as good as it gets for setting up a society. But in no way, shape, or form is it perfect, or in and of itself complete.