It's not an unique ability, you can achieve the same results with any other file type...
#ini off
[Network]
KingTomato=MyPassword
#ini end
on *:CONNECT: {
if ($readini($script, $network, $me)) /nickserv identify $ifmatch
}
...Provided that you'll always put the INI group before everything in the file, so $readini wouldn't completely mess up your script where it finds chars like '[', ']' and '=', searching for sections and items.
(Group usage is just a precaution, hopefully you wouldn't really need one)