Comment by cyphar
You cannot charge extra for distributing source code in this way under the GPLv3 (or any version of the GPL, for that matter -- there is a carve-out for physical distribution that lets you charge for shipping, but that doesn't apply here). Section 6(d) explicitly says this:
> You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways: d) Convey the object code by offering access from a designated place (gratis or for a charge), and offer equivalent access to the Corresponding Source in the same way through the same place at no further charge. [emphasis added]
That bit in the FAQ is describing the situation where the software binaries are being sold for a fee -- in that case, the GPL only requires you to provide the source code (for no additional fee) to the customers that bought the software from you. In fact, is the case in general that the GPL only requires you to provide source code to the same people you gave binary copies to -- the FAQ is just clarifying that that GPL does not require you to publish source code in public (the FSF considers such licenses to be non-free). This game is available for free to the general public, so this situation (and the text from the FAQ) do not apply -- they need to provide the source code to everyone that they distribute the binaries to.
The need to disallow charging extra for source code is obvious -- if distributors were allowed to charge for source code, they could fork a GPL project and then charge $1B for the source code, making the code effectively proprietary.
> This game is available for free to the general public, so this situation (and the text from the FAQ) do not apply -- they need to provide the source code to everyone that they distribute the binaries to.
They don't need to do anything the GPL says if they're the sole copyright owners. People are bound by the GPL because copyright law normally prevents them from distributing works without the author's permission, and the GPL is the only thing that allows them to do that.
The GPL itself even points this out explicitly in section 9:
> You are not required to accept this License in order to receive or run a copy of the Program. [...] However, nothing other than this License grants you permission to propagate or modify any covered work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a covered work, you indicate your acceptance of this License to do so.
Another way to look at it is this: the only people able to take them to court for violating the GPL are themselves.