Folks, firstly, please don't be that "well actually" guy, if someone is asking a question, answer the question, be helpful with the community, don't do what you are trying to call someone out on.
But I digress.
If a player says they are going AFK because of X, Y and Z then please submit the replay in a CS ticket for "Unsportsmanlike Conduct."
That being said, just because you may see someone go AFK, doesn't mean they meant to on purpose. This could be happening for any number of reasons. Real life aggro is primary! Many of us have lives outside of gaming and often those things can pull us away at a not so great time.
Their internet could have crashed or the game itself, these things occur.
At the end of the day, send in CS reports if someone actually says they are going AFK and let them sort it out.
-Hapa