"Xenophon notes the accepted practice of treating slaves as domestic animals, that is to say punishing them for disobedience and rewarding them for good behaviour.[130] For his part, Aristotle prefers to see slaves treated as children and to use not only orders but also recommendations, as the slave is capable of understanding reasons when they are explained"
There's plenty more. I think you're being a bit rosy-tinted here. Some like josephus did ok https://en.wikipedia.org/wiki/Josephus but many slaves got worked to death.
Seems it depends https://en.wikipedia.org/wiki/Slavery_in_ancient_Greece#Slav...
"Xenophon notes the accepted practice of treating slaves as domestic animals, that is to say punishing them for disobedience and rewarding them for good behaviour.[130] For his part, Aristotle prefers to see slaves treated as children and to use not only orders but also recommendations, as the slave is capable of understanding reasons when they are explained"
There's plenty more. I think you're being a bit rosy-tinted here. Some like josephus did ok https://en.wikipedia.org/wiki/Josephus but many slaves got worked to death.