Let me try again to summarize or reformulate my positions. I don't think we really have any disagreement here - I think our views on this are probably rather similar.
Legally it is allowed to redistribute GPL'ed software for any fee, regardless of whether you're the author, have the authors' permission, or are completely unrelated to the project.
In my opinion, it is however not always morally right to sell other people's software for profit. Maybe I disagree with the FSF on that point.
Whether or not it is morally right depends on whether or not you are "taking advantage" of other people's work. I guess it is hard to define exactly what that means, since obviously the authors of GPL'ed software don't mind their software being redistributed, so that is not the issue. They probably don't want to profit from selling it themselves either, because then the GPL is not a good choice of license in my opinion (unless you're selling more than just the software itself, like support etc).
I have the feeling that selling, say, Debian GNU/Linux DVDs for a profit, assuming the profit goes to the maintainers of the distro or to GNU or something like that, is not morally wrong.
I have mixed feelings towards something like requiring a payment before you can download Debian from their website - I somehow feel that the download should be available free of charge, even though admittedly there are nonzero costs to hosting so there is no principled reason to treat it differently from DVDs. So if that would happen, I would probably not loudly protest against it, but I would at least raise an eyebrow and maybe switch to a different distro and encourage others to do the same.
I have the feeling that if someone takes a single program, say, a GPL'ed emulator written by Exophase, and sells it on some appstore, without Exophase's consent, for his own profit, then that is morally wrong.
There are grey areas between these extremes, and I cannot define a clear line separating "right" from "wrong" here. But at least the nice thing about the GPL is that anyone, not just the original author, can make the program available free of charge as well. That should limit the amount of "taking advantage of" that can actually happen in practice...
... at least in theory. Sadly, there seem to be plenty of people willing to pay anyway, and thanks to the "walled garden" approach of the iOS appstore and Google Play, it becomes easier for exploiters to profit from other people's work and harder for friendly people to share in an effective way (since that means you have to pay for a dev account and maybe even then Google or Apple can still reject your upload, even if it is perfectly legal).
Who is to blame for that situation? In my opinion, mostly Google and Apple for creating the walled gardens that enable such nasty behavior (and profit from it too). Also of course the people who sell other people's software. But also, to a (much) lesser extent, the people who choose to be walled-in (mostly they don't really get to choose though, especially if they're not tech-savvy) and who choose (probably not knowingly, but still) to pay some scammer for software written by someone else, and who then choose to not share what they just bought (maybe because they don't know how and/or that it is legal to do so). That's what I meant when I said "stupid" and "spectacularly bad at sharing". But I agree that I shouldn't have focused that much on "blaming the victims" - the creators of the walled gardens and the ones who profit from selling other people's software are obviously much more to blame.
Now mind you, I hardly think there's any call to follow FSF's philosophy wholesale or not, as if there's claim it all comes from some divine source, it's just that it somehow often ends up being portrayed that way anyway. I guess the thing I really wanted to and should have said is that that article may seem over the top but I have yet to find an FSF article that doesn't.
