The clause about the items being donated or destroyed is new (as in, new to me - I read the T&Cs quite thoroughly when the feature was introduced, and went back to them several times over the following year or so when threads popped up here in the forums to discuss problems with it - they always said the package would be returned to the seller, but it's been quite a while since I had a reason to read them so I couldn't say if it was introduced recently or a year+ ago). It's interesting to me that this has developed as the solution to a problem that likely occurs relatively regularly (imagine buying something expensive and then experiencing a life event that prevents you from being able to collect an item, it gets given away and you're not eligible for anything except the knowledge that someone else is enjoying the item you paid for. At least if a package is RTS, the seller would generally have the means and an obligation to provide a solution for the buyer, but this means the seller is put in a position where it may be impossible for them to assist or provide a solution - I would feel horrible if I were the seller in those kinds of circumstance and it was an item I couldn't afford to refund or replace, despite it not being my fault or responsibility).
And on that note, since the issues of morals and ethics have been raised - and I want to make clear that this is my personal opinion, and I'm not sharing it because I expect other people to feel or think the same way (see my earlier response of "not your problem"), more because it's what I genuinely think and apply to myself, and maybe it'll add something to the discussion - in my capacity as a seller or buyer, I would never feel comfortable washing my hands of a situation without the express encouragement of the other involved or affected party. The way I see it is that I have entered into an arrangement with someone, it didn't go as expected, sure, but I took on the responsibility of that when I made the decision, since while I expect everything to go as planned, I know that not every purchase does - in a nutshell, I will follow through with what I feel are the responsibilities I agreed to from the outset, at least in so far as I am able. In this particular scenario, I [probably wouldn't feel the same obligation with regards to the replacement package, since that was not requested, but I would also think about what the seller was trying to do to assist me in the situation, at their own expense, and again if it were within my capabilities to assist them, I'd still do it.
I don't personally see any point in telling myself I shouldn't have to, as I know when I say that, often it's just another way of saying I don't want to, but including both a subtle ackowledgement of feeling some kind of obligation to from somewhere, and the attempt to justify not wanting to.
Still, if we're talking about morals philosophically, there's an argument that something can only be unethical or immoral if you have the ability to not do the immoral or unethical thing, and some argue that free will is an illusion - that is what you do or do not do is not actually a choice. If you accept both of those premises, nothing is unethical or immoral. 
