Earlier quoted context omitted.
To me the biggest case is going places where I might have an unexpected peripheral need. For instance, it's not uncommon for someone to need to transfer me some files with a flash drive. If I were to buy this thing, I'd have to carry a USB Type-A dongle all the time , just in case. Rather than have say... an extra millimeter of thickness, and the USB port just built right in.
I'm fairly sure it wont be too long before they come out with USB/USB-C flash drives. I've already seen several USB/Micro-USB drives.
Why would they go out and buy new ones to fit in certain models of laptop if the limited capacity and slow speed hasn't already gotten them to replace it?