Bart, you have taken the gift analogy in a too literal sense, but it's
just an analogy, and it may have its flaws.
Instead of a gift, I see it more like a fruit that you take from a tree.
The tree definitely does not expect anything from you in return, and
you don't owe anything to the tree. The tree is not creating a
personal relation with you, and you are not creating a personal
relation with the tree.
The tree has a lot of fruits for you to take. Some of them are mature
and good to eat, some of them are not. It is you who decide which of
the fruits are good for you, not the tree. You would never blame the
tree after taking a fruit which is not good to eat.
Also, if you like the fruits from the tree, you might want to care
about the tree, so that it gives more and better fruits, but this is
in no way required, because this tree is very special and taking a
fruit from it does not make the same fruit unavailable to anybody else.
Now, if you can explain how you can make a tree "liable" or "responsible"
for producing a fruit which was not mature enough for you, I'm sure
that it would be a very interesting read.
So I would really forget about the gift comparison, as I think it
didn't work for you to understand the issue.