Indeed it is. It's about reducing order cancellations by diluting the uncomfortable feeling of "buyer's remorse" associated with a big-ticket purchase.
I mean, how can anyone feel any remorse, whatsoever, from a non-committal pre-pre-order? It's like a nothing commitment.
But in the meantime, you're being won-over by the thought of having a "privileged" place in a queue that cost you nothing (nothing right now, of course).
Bottom line is it gives you time to gradually get comfortable with blowing $1K+ on a phone.
Very clever. Artful even.