It should be noted slaves were purchased from BLACKS who'd captured them in the african bush....so the slave trade wasn't considered "racist" from it's origins. Southern plantation owners considered them little more than livestock to be worked. So it wasn't a lack of conscience on their part....most southerners had little reason to mistreat their slaves; they were too valuable.
(My bold)
Except that as the Black slave population outnumbered the masters, the fear of riot, rebellion, etc. led to forbidding teaching slaves literacy. & breaking up Black families, stripping new slaves of their language, culture, leadership. Branding, whipping ... yah, other than that, it was a lot like summer camp.