When I first went to the IKEA Shanghai a few years ago, I was frustrated at how difficult it was to shop there. IKEA is setup to make you walk through the entire store. There is not shortcut to get to the checkout.
This problem becomes enormous when 90% of customers (lots; imagine christmas time mobs of people) are walking around as if they've just arrived at Disney World. Your trying to shop. They're casually strolling about getting in the way. Its a painful and slow shopping experience.