Not missed, just not topical to my reply.

That said, passengers have some tolerance for spending at the airport. Wringing it out of them cheaply is better than wringing it out of them at great expense. Using existing space, rather than building genuine concourses (the future use) that only have some retail space is a huge savings. As well, when that future expansion occurs, the Great Hall will still be a retail space, while D/E will not.