Hasn’t Arrowhead always had seats everywhere?
Yes.
When they did the renovation, they did some sweet things with seats tied to the skyboxes.
The reality is, put in seats at the Bill, you lose seating capacity. Depends how attendance and sales go in the future if they were to ever consider this (if it will help boost waning sales, and they can charge a premium price, it might happen - but man, for young people with kids, it will make games even tougher to attend on the financial side.