While open source PDF readers have significantly improved, many people still use Adobe Reader. While Adobe has had a mixed history of supporting their software in Linux/Unix, recently they have significantly improved.
There is a well written post about installer formats on the Acroread Unix blog. I recommend just reading over the post, even if you do not use Adobe software. They have a simple list of the most popular formats (BIN, RPM, DEB, PKG, TAR.GZ) as well as minor pros and cons of each. The information really is not specific to Adobe.
When software is not open source (specifically when users cannot repackage in whatever format they like), it is good to provide information like this to educate users (customers) who may not be admins.