Allow me to paint a more realistic picture: many of those PCs are junky, dusty boxes, running some outdated version of windows, filled with bloatware and riddled with security issues. Inside them are a bunch of spinning platters just waiting to fail. And when they do eventually fail (due to wear, or a virus, et al), someone's Grandmother is going to be shit out of luck, with no way to get at her email, saved photos, or anything else.
A properly configured iPad, leveraging iCloud for device backups, photo backups, email credentials etc, solves all of these problems. And they'll even configure the iPad for you in the store, so grandma doesn't need to know how to do any of it. Do YOU want to be the poor sap attempting data recovery on a failed disk, then realizing that even if you do recover grandma's data, you've still got to go buy a replacement drive, find a copy of windows that grandma knows how to recognize, and install everything exactly as it was before you got there? I've been that guy before, in both a personal and professional capacity. You will eventually fail, memories will be lost, tears will be shed.
We must not gloss over the fact that the iOS ecosystem does solve some very real pain points for real people.