1) It is possible for many to work their way through the labour ladder and find good life.
2) “The System” can incentivise corporations to maximise transfer of wealth towards the top brass without incentivising it to raise wages any more than only to keep people from leaving.
And they can do that without being exploitative. People go to their bosses and ask for more money. Some percentage of the time they get it.
If you were in business for yourself you would have to negotiate your own prices. Being employed isn't really different, just the risk is much less. You're trading something away for the security of a regular paycheck.
And they're still not being exploited. You're describing people that cannot fend for themselves. Also not everyone you're describing is only receiving basic sustenance. A lot of people in this situation live reasonably middle class lives.
They shouldn't do it too much, or then society responds in various ways (unions, legislation, etc.), so in that sense it's much like shareholder value. The company owners cannot write themselves a bonus equal to the entire profits of the company, or the shareholders will get mad. But they can certainly write themselves generous bonuses nonetheless. They don't have to completely maximize shareholder value, or completely minimize exploitation; they just have to do enough.
Those of us who actually grew up with nothing and suffered through minimum wage labor and were able to change our class and turn our lives around through labor look at you people like you're from another planet.