[nh2]

You ignored the

> and keep it all to themselves

bit. The GPL allows you to make modifications to software, and then not publish the code of those modifications, as long as you don't distribute the software. If you only use the software in-house, you can make unpublished modifications as much as you like. That's what "keep it all to themselves" most likely referred to.

[charcircuit]

You can distribute the software and still not publish it. The source just has to be available to who you distribute the binaries to. It could be the case that your community is non technical and don't care about the source code. It could be the case that having the changes is "cool" and leaking them to be public wouldn't make it cool anymore and could get them kicked out or shamed.