https://www.reddit.com/r/UnethicalLifeProTips/comments/1e37dya/ulpt_how_to_get_a_brand_new_iphone_for_only_29/?rdt=51589
ULPT: How to get a brand new iPhone for only $29
Recently I cracked the back glass on my iPhone 13 Pro Max, so I took it into the Apple Store for repair. They quoted me $29 because I had AppleCare, and told me to come back in 2 hours. However, I found it really suspicious that they told me I needed to backup everything as they would wipe my phone, when it was only physically damaged.
Anyways, it went smoothly, and I got my “repaired” phone back. Except it was brand new. The battery capacity was at 100%, the software was new, and I even got the 3 months free introductory subscription offers that you only get when you buy a new phone.
So yeah, basically what I learned from this is that if you take your phone in for repair under AppleCare, they will just give you a new phone under disguise that its been repaired.
Why do they do this? Given the difficulty and time it takes to disassemble, reassemble, and storing the inventory of the parts of the different generations of phones, I’m guessing its much more cost effective just to keep an inventory of old phones and give customers those.
So if you want a new phone, just make sure you have AppleCare, break the glass claiming it was an "accident", and take it in for repair at an Apple Store.