"It [Affero GPL License] has one added requirement: if you run the program on a server and let other users communicate with it there, your server must also allow them to download the source code corresponding to the program that it's running."
I understand the reasoning behind AGPL and on the surface it seems like a good idea, to stop the parasitic behaviour many have towards FOSS. But there are many situations where you have very legit reasons to avoid it. Even in this case, AGPL would put you in a delicate position where you need to immediately disclose the changes you made without respecting the non-disclosure period for mitigation.
It's a licence that tries to solve the problem of the GPL going obsolete when many companies no longer distribute software, but rather services based on the software (like Google or Facebook) and they can basically get away with not giving anything back at all to the community work they built upon. But this is very hard to regulate and as a result AGPL is often so cumbersome that AGPL-licensed code is strongly avoided, and it's also extremely hard to enforce when the service simply doesn't release any code or software.
Enforcement is hard, but AGPL is strictly stronger than GPL which doesn't evenninvitr enforcement on sharing server code.
Yes, many companies avoid AGPL software. That isn't a problem for AGPL-leaning authors, that's the point.
There are many reasons why AGPL is used in extremely few projects of any relevance, compared to other GPL licences, or BSD, MIT, etc.
Now, to prove that someone is running AGPL software and that they have modified it, that seems pretty hard in many scenarios.
http://www.gnu.org/licenses/gpl-3.0.html
Software is protected by copyright by default, meaning you can't make a copy. A license is a limited waiver of copyright that grants permission to make a copy, if the conditions of the license are met.
[0] http://blog.garrytan.com/goldman-sachs-sent-a-brilliant-comp...
Such decisions often happen at the engineer level, and it isn't for money management reasons, but rather "avoid purchasing and requisition BS, followed by licensing compliant BS" reasons.
I'd go so far as to say "nearly all of them."
iXSystems does a lot of cool community work via FreeNAS, PC-BSD and FreeBSD.
Github (Ruby), thoughtbot (Ruby), Google (Go, Python), Dropbox (Python), AT&T (C++, Ruby), Zurb (Ruby, Foundation), Twitter (Ruby, Scala), ...
missing a bunch and some platforms too.
Otherwise, the AGPL would never have seen the light of day.
So, it's also not true that "any employee of the company can publish the modications to the GPL-licensed code".