You know it takes like a minute to convert mobi to PDF, right?
http://www.convertfiles.com/convert/ebook/MOBI-to-PDF.html
Same goes for everything except the "enhanced" versions. I have a couple command line tools that can deal with DRM protected reader files as well.
If the concern is about copying the file from a device, that's trivial. I know
GW should be releasing things in the format you want to see them, but this would be smallest of all disappointments I have had to become accustomed to in many years of being a customer.