if the original licences for these products was the GPL (GNU General Public Licence), how is it, that, these are sold for a fee (although the fee is minimal)?
As we have said elsewhere more clearly, it's perfectly OK to sell GPL software: that is, to charge for the conveyance of the binary. What the vendor may not do is refuse also to transfer the complete corresponding source code to recipients of the binary, or to further charge for that. Essentially, one must convey freedom along with the product.
Whether the vendor in the above example(s) will give you all this on request will not be known until someone who's paid for the binary asks for it. I have my suspicions, but that's all they are.
Have there been changes to the GPL version 3 that supersede version 2 allowing the executable from the free code, free for copying and redistribution, to be sold at a fee
No, GPLv2 allowed this also.
Why the fee?
The Play store provides a mechanism whereby people can monetise software. Economically speaking, it's probably unavoidable that some people will ignore the "I can charge for software I wrote" model, in favour of the "I can charge for software somebody else wrote" model; the overheads are lower.
Essentially, am I just paying compilation and distribution?
Not even that. You can have single-click access to some five thousand (at time of writing) free software apps for Android via the F-Droid repository, and its corresponding software management app (or equivalents). Because it's specifically for free software, the issues of charging and privacy don't arise (no authentication is required, unlike Play Store), whereas the licence choice and app-related privacy issues are mentioned front-and-centre (at least in the official app). You can run an entire de-Googled Android phone off this repo; I have, for many years.
Somebody once said (I'm sorry I can't find a link offhand) that proprietary software requires you to pay, while free software requires you to learn. One could see this whole exercise as an excellent illustration of that principle.