[AnimalMuppet]

I could agree with almost everything in your last paragraph, but you're still using loaded words. "Appropriated", for instance. Even "unpaid" carries (perhaps just to me?) the implication that it should be paid.

I would describe the same thing like this: The workers plus tools (capital) create value. The workers don't get all the value produced; capital also gets a cut.

You can say that this is morally right. Or you can say that this is necessary, because the capital isn't invested out of the goodness of the capitalist's heart. We have to give them some payback if we want them to buy the tools. The alternative is to have only the tools that our in-house workers create, which is usually a sub-optimal situation.

Now, any given situation can still be exploitation of the workers (in the common rather than axiomatic sense), and still be morally wrong.