I know what ya mean and hopefully you understand what I am about to say, you know.
The stadium was built with football in mind and it's always had a removeable pitch. It's a thinly-built stadium so I don't think there's much room to make wide unless they made the corner entries like extremely angle. I am sure there's a FIM standard white line distance too. If you look at the pics at the very start, they have built the track right up against the start of the seating plus the air fence to come.
I think looking through them, I understand what ya mean. They could have gone more in the middle. You know?