Purchasing an iPhone 6/6+ required precisely this process, an online reservation. There was no reason to even visit the Apple Store if all you wanted was an iPhone 6. Every morning at 8:00am (usually between 8:01-8:02am) pretty much all of the phones for the day would be reserved. Sometimes a few might be available at, say, 3:25pm, but it was rare. And the reservation system was designed to block out robots, but it was very annoying, involving Apple ID sign-in and then 2-step SMS verification and then choosing whatever model was available after all those delays. I ended up purchasing one from a scalper outside the Apple Store in Causeway Bay, Hong Kong, for about 100 US over nearly three months after the release. The reservation system worked best for scalpers, who managed to catch dozens of phones using the reservation system every day.