I'm suggesting it is, test the logistics but with a capacity of 100k there is plenty of flex for 2 games that draw 30k crowds, you dont allocate 2 people to one seat.
Do it ar Docklands & fill the place, yes some will miss out.
I'm suggesting it isn't and not from a capacity issue. Clearly from a capacity issue it would be fine and if you were going to do it one group of supporters would be cleared out before the next is let in. Why charge someone more if they are only interested in one game? And really, what is the benefit? Staff still need to be paid, food and drinks still need to be stocked, electricity is still paid for.
If there was a benefit I think it would already be happening.