With 7 hours its pretty much a non-issue anyway - with so much time, and as long as it isn't a late night connection, I would suggest you do properly enter Hong Kong and visit a nearby mall (in Tung Chung or the ill-fated 11 skies right next to the airport), or check out if something is happening at the Asia World Expo. If you're on the ~5pm HKT-HKG arrival (going thru to a midnight Sydney flight), with no status, and presuming not on a very tightly constrained budget, I would exit the airport and get a public bus (non airport) to the Tung Chung cityplaza mall, have a nice Hong Kong dinner there, then come back, probably taking 3-4 hours and stretching your legs. Rather than spending 7 hours with fairly mediocre food in the airport itself.