A chore isn't slavery, picking crops at some farm 8 hrs a day, 7 days a week with no pay is. I'm not sure why you're fighting so hard to deny this...
Because I don't care. If they are out picking crops, I don't have to pay for their cable television. People who have committed crimes should not be benefits to my slave labor. The several hours I work a dry for free because my wealth is confiscated to buy them extravagant things.
Forced labor is forced labor. Because you call it a chore doesn't make it any less forced labor.