When I visit a mall it is obvious that shops such as 2 degrees, Spark, and Vodafone are busy and actually selling stuff.    However, if you sit down at the food court for a coffee and watch some of the small speciality shops it's a different story.    Some of those shops will have 2 or  3 staff, and often in a 15 or 20 minute period they might sell nothing at all.    Almost always they will have a few people wander in browse and leave.   You get a feeling for how much they would have to sell in an hour just to pay for staff wages, let alone the mall rent, compulsory shop refits and the like.   I guess Westfield have calculated rents versus 'churn' of retail spaces & have it fine tuned to their maximum advantage.