Modifing a preference via applescript changes file group
In short, it doesn't matter.

ls -l print out consists of status (10 character), number of links, owner, group, etc.

Of the first 10 characters describe file type(1), owner permission(3), group permission, and permission for others. In the case of

 -rw-r--r--  1 root  wheel


File type: - means regular file.

Owner Permission: rw- means user root can read and write.

Group Permission: r-- means user(s) in group wheel can read only.

Others: r-- means user(s) not in group wheel can also read only.

So you don't have to read the rest to know there is not security risk for what the group is.

So what are the users in wheel, admin and staff?

$dscacheutil -q group -a name wheel; dscacheutil -q group -a name staff; dscacheutil -q group -a name admin


You get:

name: wheel
password: *
gid: 0
users: root 

name: staff
password: *
gid: 20
users: root 

name: admin
password: *
gid: 80
users: root YourUserNameHere


wheel is a legacy thing from UNIX. OS X never bothered to change it. When you sudo the file, sudo automatically use group staff. If you don't want the group name to change on the file, do:

sudo -g wheel defaults write /Library/Preferences/com.apple.alf globalstate -int 2