Traditionally, the root account (account 0) is not used for daily tasks. This is widely known; however, this is the reason that root’s home directory was usually / (the root directory) as there was no need for .profile, .login, .Mail, and so forth. The root account is even created under MacOS X with a locked-down password (that is, there is no valid password for root, making it impossible to log in as root).
However, this is most certainly not the case today – and more and more administrators use the root account for many tasks. One common problem is the problem of someone wanting to change the root shell – and then breaking the startup process since some scripts would assume that the shell is the Bourne shell. This was more of a problem under BSD since the standard BSD shell was the C shell, and the startup scripts usually assumed the Bourne shell (which is completely incompatible with the C shell). The toor account (that is, root spelled backwards) was created for this purpose: a person can log in as toor and have the C shell (csh), but not affect the standard startup process. A toor user would still have the userid zero (0) but would for all intents and purposes be the root user.
This would also lead to the possible creation of a specific home directory for the toor user.
In MacOS X, the root user is locked down and no login is possible as root. To access root, the sudo utility must be used as the admin user (which should be the user that installed MacOS X).
The wheel group is also part of this process; using the wheel group can expand the capabilities of some users in order to further reduce the need to actually use the root account as a shell account.
Thus, you can see that there is really no reason to use the root account. But is that going to stop us? Perhaps it should…