It's not useless to other ZIP programs: you can unzip and zip back the directory with other programs and it will work just fine. The reason? They didn't make a

It's not useless to other ZIP programs: you can unzip and zip back the directory with other programs and it will work just fine. The reason? They didn't make a derivative format. Of course OS X aliases won't work on Windows -- there's no such thing as alias on this operating system. Just like Windows won't magically set Unix permissions on files extracted from ZIP archive created in Unix format. OS X specific things will be useless on other OSes.