That sounds like dogma. Why not? Actually it does exist. Everything is free lunch. It has existed for millions of years. The rather failed attempt to deny free lunch to the world, will gonna have to end soon. Moreover, there's absolutely no justification for what is give and what is take. Yeah, some interaction exists. And? Who says what is what. You can work for someone, do great things for them, and they could claim you are the worst person in the world, and you robbed them. And this happens, all the time.
I prefer free lunch, instead of free psychopathy - which is inevitable product, otherwise. It's either free lunch; or Orwell, in order to prevent injustice. Probably nobody in their right mind would like to live in the Orwell scenario. By the way, even Orwell himself believed that free lunch is quite possible. And note, there's nothing wrong with free lunch; people's highest achievements are not motivated by chasing lunch. If you work in Google, or if you are a tenured researcher, you get free lunch; you even get free laundry. It doesn't seem to hurt such people, on the contrary: it frees them to be even more creative. We have so much free lunch all around us already. We can't hide from it, even if we wanted, and we can't pay for it. The air we breathe is free, and we walk the roads and we use the infrastructure, and we get the opportunity to read the books of generations. This is neither unethical of us, nor demoralizing for us; in fact, it is highly positive and stimulating.