I remember once at my old high school they had a digital version of the math textbook and a code since my school was too poor to buy physical books for everyone and they had to stay in class.
I forget what publisher but the book would never load in Apple's preview, I think maybe due to it having a password or DRM? So they're are still probably rare reasons to install Adobe Reader on a Mac.
I usually don't make comments regarding other people's software choices but you are definitely doing it wrong.
Mac OSX's built in pdf viewer "preview" is much better than even adobe's reader even though they invented the format.
The entire rendering system of OSX is based on postscript so it flies.