You get paid for doing a job, slaves don't get paid so it's not a job, it's more like a hard labor prison sentence, certainly not a job.
You don't get killed if you don't pass an exam, so that's not really a relevant comparison, and the hole as far I have found is the only route for slaves not to be slaves (other than the revolt), so it's not suprising those abused who can't take it any more would select to risk their lives in order to be 'free'.
The steel yard, why aren't the slavers with all their amo clearing out the trogs and getting the steel themselves? Shall we agree it's easier to just send slaves in, save amo (which isn't a problem to the slaves because of the press), but amo is clearly more valuable to the slavers compared to people.
For me a leader that allows this sort of thing to happen is not good. It's very easy to pay lip service to the lone wanderer and talk about all the positive things he does. I've said in a post previously, Ashur seems to do a speech check before he speaks to the lone wanderer and Ashur is always 100% successful and auto charms players left right and centre!
The 3 lined up and shot at the begining of the Pitt when you first enter were attempting to escape, I don't think that is a justification for execution. The poor chap in the stocks I have found is always killed by the slavers once the revolt starts, he's stuck there, can't run, clearly has nothing to do with the revolt and they kill him anyway.
Fine, not job, role. Whatever, the slavers didn't get
paid for hunting either. Besides, what are the workers going to spend their caps on? They don't pay rent, or pay for food. They're living a good life compared to most. Do as you're told, and live. Sure, they don't get the best food, or the cleanest beds, but they're surviving. More than what you can say for most 'free' wastelanders.
Plus, in peaceful, good times like we're living in, things aren't extreme, you don't get killed, you repeat the year. In Fallouts extreme case, extreme measures are taken. Why should they continue to receive free food and lodging when they aren't doing what they're told? They aren't holding their end of the bargain. As for the escapees, we don't know anything about what they did prior to their escape attempt, maybe it was their third strike or something. The guy being killed tied up was simply a scripting issue, the slavers were scripted to kill slaves, and that guy fit the bill, regardless of his predicament.
The slavers, with all their ammo and what-not need to use it for more dangerous foes, which are armed, like Wild Men, that are all over the city. They need to go out, hunt and kill for food. That's what they've been told to do. The slaves can make do, with their Auto-Axes or whatever, they can manage it. If the slaves are so useless that they can't even do the menial task of collecting steel, then they should all just be killed, I mean; this is society, this is how it works, everyone does their fair share. The task given was collecting steel.