Hacker News Reader

If sudo works the same way on Mac's as it does on Linux, then anyone in the sudoers file could give a rogue application root access.

It does, and, the only user there, by default, is the first user of the system - the administrator. Not all people use this as their main user.

By default, most do, and what happens by default is what matters to virus writers.

The file includes all password hashes, including root. So crack that, then you have superuser.

By default, Mac OS X disables the root user: http://support.apple.com/kb/ht1528

That said, reset or crack any admin's password and you can go to town with sudo.

Default user can use sudo with it's password. That's all you really need.

Not everyone, but I'd reckon MOST people do.