It's a parable wherein the landowner is the Christian god, the work of the vineyard is the work of his will, and the denarius is salvation. It doesn't have anything to do with people getting paid fairly, it has to do with the Christian god's generosity disrupting notions of fairness.
I think that, independently of the original meaning of the parable (which is not at all what we are discussing here), it indeed is a nice example of having to accept the terms you negotiated without looking at what terms others get. I used the same example to explain why I think this situation is a bit different. But it is just an analogy, nobody is claiming this is the right interpretation of the biblical text.
the parable serves to introduce the idea of fundamental dignity in contrast to conventional notions of reason and merit. and ought not be taken as youve suggested
