"The only difference as compared with the old, outspoken slavery is this, that the worker of today seems to be free because he is not sold once for all, but piecemeal by the day, the week, the year, and because no one owner sells him to another, but he is forced to sell himself in this way instead, being the slave of no particular person, but of the whole property-holding class." (Engels)
"The slave frees himself when, of all the relations of private property, he abolishes only the relation of slavery and thereby becomes a proletarian; the proletarian can free himself only by abolishing private property in general."
The idea that you can "quit at any time" is a farce; you must then find employment under someone else in order to survive, or manage to amass sufficient capital, something which is not an option for most people, especially with family. An extreme example of this logic utterly failing is in those developing nations with sweatshops.
> An extreme example of this logic utterly failing is in those developing nations with sweatshops
Poverty means making hard choices. If your choices are :
1. Starve to death
2. Work in a sweatshop
Most people would pick 'Work in a sweatshop'. Nobody who has the choice to work in a sweatshop or be a doctor is working in a sweatshop
Then it's not a choice. Therefore there can be no consent, you are not made to work by force but by threat of starvation or homelessness, it is an oppressive situation even if these people don't have literal chains at their feet.
Make no mistake, slavery also requires consent: the slave can always kill himself at the very least.
Rape is a thing, so I don't think this is a very good moral standard. Informed, active assent is the usual standard.
Many people can't. I mean, they can, but they can't afford it, unless they're willing to risk homelessness.