There's an odd moment in Attack of the Clones. Anakin and his mother are "slaves." But they live in a multi-room dwelling all by themselves and Anakin has enough free time and resources to work on both a pod racer and a DIY protocol Droid.

My theory is this: in Star Wars you are either self-employed (like Boba Fett or Max Rebo), part of a military or quasi military organization, a business owner (like Dexter Jettster), or... you are a "slave."

Their definition of "slave" ranges anywhere from literal chattel slavery all the way up to anybody who is employed for wages, the alternative to which is dying in the street. Their language just reflects the raw reality that it's only a matter of degree that separates chattel slavery from wage slavery.