> There is a long history of people deliberately selling themselves into slavery.

Then think about how bad their alternatives must be

I will say this about Walmart, despite what you say about conditions and low pay, they are still above the board compared to smaller employers. They follow all the labor laws, pay taxes and afford their employees all the rights required by law. The alternatives such as small employers often don't pay taxes and pay their employees under the table, stripping them of legitimacy and rights. So again it depends on what you're comparing them to