That would take a really desperate people and masochists to actually took a job like this while getting bullied. Moreover since the swordsman job is unpopular, there won't be many meat shields anyway to be treat as something expendable.
Either they actually need that meat shield for their formation (so they'll need to build mutual trust for a lasting and a working party)
or,
they can treat him as expendable because their party doesn't actually need meat shield, so whether meat shields are rare or not will be irrelevant. (which means this is not the premise that I mentioned)