No society is totally evil, and it is sophomoric to claim that about the CSA, 150 years after the fact. 150 years from now, there will be arrogant ass-holes saying that the U.S. of the 21st century was inherently evil because we ate animal flesh, and did it enthusiastically.
It was generally believed among all "White" people in the 1800's that black Africans were manifestly inferior to Caucasians. Some thought that they were a sub-species of human, but regardless, they were inferior. At the same time, it was believed that slavery, harsh as it was, was a better existence than what the enslaved people would have been experiencing in their homelands in Africa. Who can say they were wrong? The government and social leaders of the Confederacy (and the Border States) did not think of themselves as fighting to support evil, but rather fighting to prevent outsiders from screwing up their lives.
Slave labor was not "free" in any sense of the word. Slaves were purchased at great cost, or raised from infancy and maintained for years before they could do productive work. They had to be clothed, fed, and housed, and kept alive, whatever that entailed.
What a colossally stupid OP.