I still feel sudo is such an important group, that it would be good if users-and-groups.txt would be further improved to more clearly document that this group is what allows users to not only run commands with sudo and pkexec, but also execute various other polkit-1 actions like install software with packagekit. So it is now actually a rather badly named generic "administrator" group. (Some other distros apparently use other group names, like wheel for Arch.)
