Absolutely agree with you on that. I'm not missing it at all though.
1. We have always traded in our old phones for subpar money. I'm not dealing with craigslist nor ebay. Just can't do it.
2. Having the newest phone is definitely not a necessity that is for sure, but it sure will be easy to trade it in, and deal with $90 bucks a month (2 iPhone 6S Plus 128gb), then to deal with $1100 bucks at a time. That's not to say we can't afford it, but we can definitely spread the cost out over time, and in time, we get a new phone.
The sheer honesty of it is, if we could buy a new iPhone 6S Plus for $500 bucks this year, and then trade it in next year, and get the iPhone 7 Plus for like $200-$300 dollars without the hassle of dealing with selling it, and the hassle of AT&T contracts, we would do it.
But the fact of the matter is, this is the simplest and most convenient way to get a new iPhone every year, albeit, probably one of the most expensive ways.