I wasn't aware of Answers.com; that's a great counter-example! I knew of a few of the others before this comment and I've viewed them as providing some amount of service or support for the price paid so yes they are selling GPL they didn't write, but they're selling something else (their time) along with it.

There's certainly an argument that selling support for software you didn't write (or didn't write in large part) is 'bad'. I also believe that if you are selling the (free/gratis, GPL) software without support you're not going to be in business long.

And all good points on the differences between CC & GPL, my only point was that selling compiled CC-BY-SA binaries provided security-through-obscurity level protection from someone reselling your product (when paired with trademark protection).

Thank you for all the things to think about!