Because wheel is a tool of oppression! From
Why GNU 'su' does not support the 'wheel' group
(This section is by Richard
Sometimes a few of the users try to
hold total power over all the rest.
For example, in 1984, a few users at
the MIT AI lab decided to seize power
by changing the operator password on
the Twenex system and keeping it
secret from everyone else. (I was
able to thwart this coup and give
power back to the users by patching
the kernel, but I wouldn't know how to
do that in Unix.)
However, occasionally the rulers do
tell someone. Under the usual `su'
mechanism, once someone learns the
root password who sympathizes with the
ordinary users, he or she can tell the
rest. The "wheel group" feature would
make this impossible, and thus cement
the power of the rulers.
I'm on the side of the masses, not
that of the rulers. If you are used
to supporting the bosses and sysadmins
in whatever they do, you might find
this idea strange at first.
See also the Debian Reference. Anyways, the
sudo group is built in so who needs