What? Yes they do! I unpack dozens of iPhones and Macs at work each year and a charger is included every time. Now, I think this just might be a terminology mix-up as a charger is technically not an "adapter", but e.g. where I live the words are often both used for a charger. I suspect that this is what the parent comment meant.
Ah. Yes, I thought that by "adapter" OP meant micro-usb to lightning adapter, which is available, but not bundled. The charger is, of course, included in the box.