/bin are there so many Alias and Unix executable files? I thought executable files were files that Mac categorize as "not used" or along those lines?
I guess what you're confusing is how these files are represented in Finder. In Finder, the file type of binaries are shown as ‘Unix executable’. Executable files as you may know them are probably .exe for Windows, which are not something macOS can execute. They are still referred to as executable files, since just because macOS can't execute them doesn't mean there isn't something else that can.