There is an AV weekend going on which means that you get a lot of rep regardless if you win or lose. The sole purpose of this weekend is to get as much rep as possible before it turns into a mid 24/7 AV on Monday.
When you have a 99% chance of losing the BG, don't go and turtle in your base because your are wasting everyone's time, including your own team mates. Just grab your "free honor" and move on to the next game.
The reason as to why I specifically address this to Alliance is because I honestly don't see horde do this, at least not to the same degree.
Your dearest admirer, Zaft.