Why do they spotlight the ring for boxing?

This may be an odd question, but I never understood why they do it, and I've always hated it. Why, when a fight is at a large venue, do they turn out all the lights out so you can only see the ring? I want to see the crowd too god damnit! Turn the stadium lights on. Here is Hatton vs Lazcano in a sold out stadium with 55,000 in attendence, but you can't tell from watching it. It looks like shit imo.