I'm a freelance graphic designer (35+ years) and ALL my clients want the finished product and all related files for archive as well. Also, if you work in a collaborative environment, it's sometimes necessary to pass along projects to another designer. Being able to easily package any project is a great advantage and time-saver. And as you stated, it's not impossible to hand-collect all the files in a particular project—it's just time-consuming. It seems to me that not being able to package a design is a glaring omission on the part of the developers. I have to wonder if the software developers have ever worked as graphic designers in the real world. Just my humble opinion...