I do not feel the time was wasted either. I went back to that post and re-read it & all the comments I hadn't seen. I think there are some interesting points there, I also think there are some conflicts there, but to me it sounds more like a discussion than a jumping-on your lovely idea.
Some of the other ideas raised are also interesting, for example pbristow's opinion that parents owe the children they bring into the world a living until those children have learned how to provide for themselves is interesting. I'm not sure where I stand on that, actually. It makes me consider, alongside your (I still think lovely) idea, the idea of responsibility. If I accept a responsibility, do I not then "owe" the world, the community, the actions required to meet that responsibility? If I (freely, maybe even motivated by that ideal love, as a gift) give someone my word to do X, do I not thereafter also "owe" that person the doing of X?
If I bring a child into the world, a being that cannot care for itself, do I not by that act also accept the responsibility to care for & raise that child, or to make alternative arrangements for that? Of course, ideally the question of whether I owe anything (or what exactly) to that child should not come up, if I love it I'll want to care for it anyway. Still, if I die before I've been able to teach my child how to care for itself and survive, what about the child? There would be needs unmet there - and through no fault of the child.
Needs unmet, deficits... they lead to feelings of "but I didn't do anything wrong, it's not fair that the other children have X and I don't". I think that's perhaps where the attitude of "the world owes me something" comes from.

I sadly find that it is very difficult to get entirely away from the "trade" attitude, too, finding myself thinking about agreements made from free will, e.g. "I'll help you paint your house, You'll help me
make a dress" or "I've got money, I'll buy the paint, you've got the talent, you'll paint a wall picture - one for yourself in your house, one for me in mine" or "we both want X to exist, I'll do Y to help that, you'll do Z"... so long as these are made from free will... But how to deal with one person following through and the other not? Is there not an obligation that comes with a promise?
Even if it's a promise made as a gift - "Yes, I have spare time & a car, I'll gladly give you a lift to the airport tomorrow, 'cause I love you and like to see you happy" do I not then "owe" the person to follow through on the offer/promise?

It's all very muddled once I look at it more closely. But I do still very much like the idea, and I thank you for your courage to voice it and pose the question. *hug*