Great question. I don't know if it is common, but MY PARENTS DID something like that. My mom once told me (prepare to be astounded. seriously. sit down.) that white people were very industrious and they knew how to take care of themselves, and the whites had to show the Black slaves how to put in a good day's work, and save so that they would have enough food for tomorrow. While she didn't come right out and say it, what she said was pretty close to "slavery was good for the slaves." YIKES.