When you read Graeber's comments on slavery in Debt: the First 5000 Years it makes things a lot clearer. Someone who works for free isn't necessarily a slave. Someone who lives where they work isn't necessarily a slave. Even someone who can't change jobs isn't necessarily a slave. The only thing necessary for slavery is isolation. When you can separate someone from their family and friends, and anyone or anything who can support, defend and protect them, then you can do anything you want to that person. No amount of cruelty will have any consequences for you, as long as you can keep them powerless and alone.

It's the same reason abusive boyfriends fly into a rage when their significant other has been talking with other people without them. It's all about removing you from your support network. That's the essence of individualism. It's window dressing on slavery.