Is Olivander's a walmart now?
I'll give my .02..
the wizarding world has kept itself back in more classical senses in many areas of life. From their housing, furniture, dress, transportation, and even shops. In those times, shops were not franchises, they were a store owned and operated by a shop keeper. Olivander is an old man.. and from the book people flock to him directly. Not to 'one of his stores..'.
In the show today they don't try to call the actor Olivander, they kind of avoid that direct link (even though it is Olivander's Wand Shop). But I think the idea of 'franchise locations' doesn't fit the society as projected in the books... or even 'satellite offices'.
Olivander's frequently has waits longer then FJ - I'd wager they'd really want to fix this because the Wand shop = money printing shop.
They could redo Olivander's to include multiple theatres and a preshow location to help mask the fact there are concurrent shows.