>Because ethical considerations that treat each party as an autonomous agent are satisfied.

Autonomy isn't the only concern in moral actions (see cases of exploitation where autonomy is respected), and it's certainly not the only concern in justice - the capabilities approach recognizes autonomy, but it also recognizes it is bounded by structural factors outside the individual's control.

>Thats your opinion, when you're the one writing the checks, you get to decide what size to make them.

That's beside the point, though. The market (the actors within it) does not, in many cases, produce just outcomes. At the sight of an unjust desert, telling someone that they can decide to be just if only they were in that position is irrelevant to the issue of desert that has already occurred. Unless your position is that every result is deserved (which seems very hard to defend), there's room for more than one subjective opinion, and me writing one check won't fix it.

>In a free market, when each party has the ability to terminate the relationship, then both parties are equally powerful in their ability to walk away.

Each party has the ability; in many cases, only one has the capability. It's a structural issue with many employers and a far greater number of employees. Something being mutually beneficial or a Pereto improvement doesn't motivate me at all, because even mutually beneficial arrangements can be exploitative.

>Yes and the employee has the capacity to make much more money because of their access to capital that they aren't responsible for

This is irrelevant to bargaining power; the employee can barter with his skills, of course, but not if they're replacable (at a low cost or otherwise).

>Its unclear to me why you would even be in a position to tell two parties that their mutual employment transaction was exploitation without knowing the specifics.

I agree, but the definition of exploitation as generally agreed upon or argued for is not "subjective". I'm not sure what the two parties or their mutual employment has to do with whether or not there is exploitation.

>sleight-of-hand about calling employment "slavery" and chattering on and on about being forced to toil in a factory on some fatcat's toolroom lathe

You're right, I don't think it's slavery or comparable to slavery. I think capitalism is a massive improvement on feudalism and on sharecropping.

>and when you point out that lathe operator is a skilled job making well over a living wage

Most exploitation-theorists would say the wage is in many cases irrelevant. It being a skilled job isn't that important. The issue is employment in cases where bargaining power is low (structurally or caused by an actor). Starvation is only the worst case.

>without allowing them the basic human right of deciding how much their labor is worth.

They don't decide that, it's "decided" by the market - and by extension society in general. I'm also not sure why it would be a human right to decide that. You can make all the decisions you want - and someone with more power can override them. If I dedide my labour is worth $100k, I'm laughed out of every office I step into. What use is the right?

>Its just a biological/physical set of facts that you want to stay alive, you need to eat to stay alive, and someone has to make the food.

By this metric there is no such thing as a "need". That's ridiculous, or I'm misinterpreting you.

>In a planned economy, only those with the planners' permission can make food.

I don't argue for a planned economy (in the traditional sense; I'm still working out my thoughts), but this isn't really true in the Marxian idea of a "planned economy".