The whole "slave class" is total bullshit. This is another perception that we once believed in, and active JW's still believe. In fact, as is the case with just about every teaching of the watchtower. It is in fact the opposite. The lower you are in the ranks, the more you are a slave. Although we were led to believe that the higher you are in the org, the more you are a slave.
You will never see a member of the GB in coach class on a plane, nor will you ever see any of them "bunking" at a JW's dwellings.
Although, I think the CO still bunks at a JW's dwelling. However, in order to have the "privilege" of this, one has to be of a high spiritual standing. There is nothing, and I mean nothing that proves this organisation are footstep followers of Jesus's.