They actually have a YouTube video explaining their reasoning behind it:
I completely sympathise with those who are disappointed about this, and I am concerned about firms taking the political correctness/positive discrimination stance. (I understand their year 11 are aimed at state school students, and to be fair giving AC's to candidates they know from first year schemes is understandable.)
Regardless of your opinion about this however, recruitment is a two way process and if you don't agree with their policy, then you probably aren't missing out much by not working for them.
Hope we all get to work at a firm that value us